How do I make assets, make enemies come in waves and title screens?

You have to learn to program. Read the documentation, do some tutorials, rinse & repeat until you have sufficient knowledge. Then it's pretty easy.

To be more particular, the question you have asked is impossible to actually answer, since there are an infinite number of ways to do those things, which vary depending on what effect exactly you want. If there's anything specific that you need help with, then feel free to ask, and provide code that you're using.