How do I make my pygame levels more efficient?

I've been redoing a lot of my game in order to make it more efficient, before I had functions for each level and it had about 300+ repeated lines of code for each level, I've taken it out however I'm trying to get level one to function properly now. Below is my code, any help as to how to get my code to play level1 when I run the game as right now it only displays the background screen and none of the enemies, platforms or the character.

import pygame
import time
import random
from pygame.math import Vector2 as vec

pygame.init()

# Set the screen size
screen = pygame.display.set_mode([700, 500])

# Define the colours for text
black = (0,0,0)
white = (255,255,255)
green = (0,51,0)
light_green = (51,102,0)
PLAYER_FRICTION = 0.0
PLAYER_ACC = 3
HEIGHT = 500
WIDTH = 700
FPS = 60

# Set Display

pygame.display.set_caption('Jungle Blast')
clock = pygame.time.Clock()


class Character(pygame.sprite.Sprite):
    def __init__(self):
        pygame.sprite.Sprite.__init__(self)

        self.image = pygame.image.load("TheoHills.png")

        self.rect = self.image.get_rect(topleft=(50, 300))
        self.x = 50
        self.y = 300
        self.pos = vec(50, 300)
        self.vel = vec(0,0)
        self.acc = vec(0,0)


    def characterJump(self,platforms):
        self.rect.y += 1
        hits = pygame.sprite.spritecollide(self, platforms, False)
        self.rect.y -= 1
        if hits:
            self.vel.y = -18

    def update(self):
        self.acc = vec(0, 0.5)
        keys = pygame.key.get_pressed()
        if keys[pygame.K_a]:
            self.acc.x = -PLAYER_ACC
        if keys[pygame.K_d]:
            self.acc.x = PLAYER_ACC

        # apply friction
        self.vel.x *= PLAYER_FRICTION
        self.vel += self.acc
        self.pos += self.vel

        self.rect.midbottom = self.pos


        if self.pos.y == 500:
            background_image = pygame.image.load("Lose Screen.png")


        if self.pos.x > 699:
            level2()

class Bullet(pygame.sprite.Sprite):
    def __init__(self):
        super().__init__()

        self.image = pygame.image.load("Bullet.png").convert()
        self.image.set_colorkey(black)

        self.rect = self.image.get_rect()

    def update(self):
            self.rect.x += 10

class levelInd(pygame.sprite.Sprite):
    def __init__(self):
        pygame.sprite.Sprite.__init__(self)
        self.image = pygame.image.load("1 out of 5.png")
        self.rect = self.image.get_rect(topleft=(20, 20))
        self.pos = vec(20, 20)

class Platform(pygame.sprite.Sprite):
    def __init__(self, x, y, w, h):
        pygame.sprite.Sprite.__init__(self)
        self.image = pygame.Surface((100, 88))
        self.image.fill(black)
        self.image = pygame.image.load("Platform1.png")
        self.rect = self.image.get_rect(topleft=(x, y))

class Enemy(pygame.sprite.Sprite):
    def __init__(self, x, y):
        pygame.sprite.Sprite.__init__(self)
        self.image = pygame.Surface((100, 50))
        self.image = pygame.image.load("RobberStanding.png")
        self.rect = self.image.get_rect(topleft=(x,y))

def draw_text(surface, text, size, x, y,font_name):
    font = pygame.font.SysFont(str(font_name), size)
    text_surface = font.render(text, True, black)
    text_rect = text_surface.get_rect()
    text_rect.topleft = (x, y)
    surface.blit(text_surface, text_rect)

class levels():
    
    levelind = levelInd()
    character = Character()
    all_sprites = pygame.sprite.Group()
    platforms = pygame.sprite.Group()
    enemies = pygame.sprite.Group()
    bullet_list = pygame.sprite.Group()
    background_image = pygame.image.load("JungleBackground.png")
    
    running = True
    while running:
            clock.tick(FPS)
            for event in pygame.event.get():
                if event.type == pygame.QUIT:
                    running = False
                    pygame.display.quit()
                if event.type == pygame.KEYDOWN:
                    if event.key == pygame.K_w:
                        character.characterJump(platforms)

                if event.type == pygame.KEYDOWN and event.key == pygame.K_SPACE:

                    bullet = Bullet()

                    bullet.rect.x = character.rect.x + 10
                    bullet.rect.y = character.rect.y + 50

                    bullet_list.add(bullet)
                    all_sprites.add(bullet)

                    for bullet in bullet_list:

                    # See if the enemy is hit
                        enemyHit = pygame.sprite.spritecollide(bullet,enemies,True)
                        if enemyHit:
                            enemies.remove(Enemy)
                            score1 += 10
                        if bullet.rect.x > 700:
                            bullet_list.remove(bullet)

            if character.rect.y >= 500:
                background_image = pygame.image.load("Lose Screen.png")
                pygame.display.update()
                all_sprites.empty()


            death = pygame.sprite.spritecollide(character, enemies, True)
            if len(death) > 0:
                background_image = pygame.image.load("Lose Screen.png")
                all_sprites.empty()


            all_sprites.update()

            hits = pygame.sprite.spritecollide(character, platforms, False)
            for platform in hits:
                if character.vel.y > 0:
                    character.rect.bottom = character.rect.bottom
                    character.vel.y = 0
                elif character.vel.y < 0:
                    character.rect.top = character.rect.top
                    character.vel.y = 3

                character.pos.y = character.rect.bottom


            screen.blit(background_image,[0,0])
            all_sprites.draw(screen)
            pygame.display.flip()
    

    def level1():
        
        done = False
        clock = pygame.time.Clock()
        font_name = pygame.font.match_font("Arial")
        black = ( 0, 0, 0)
        white = ( 255, 255, 255)
        x = 300
        y = 88

        e1 = Enemy(250, 125)

        enemies.add(e1)

        all_sprites.add(character)
        all_sprites.add(levelind)
        all_sprites.add(e1)

        p1 = Platform(-80, 400, WIDTH - 400, HEIGHT - 10)
        p2 = Platform(175, 210, WIDTH - 400, HEIGHT - 10)
        p3 = Platform(500, 400, WIDTH - 400, HEIGHT - 10)

        all_sprites.add(p1, p2, p3)
        platforms.add(p1, p2, p3)

        score1 = 0

    level1()

This is the image that shows up whenever the game is run.