Need help for my college project

Hello, I am new in creating games and I want to start with a 2d game for my college project with just 2-3 levels. I want a platformer game in which a character can run jump and strike enemies. The character and enemies should have a HP bar. The character should also level up after completing a level. The level should have a ground, and enemies spawning when the character progresses. Please help me what and how to do it

Check out this tutorial goes through making a simple platformer.