How hard is it to make games?

I just registered here. Came here to learn how to make games. I just have a few questions: how hard is it? How long will it take on average?

You will need to be a lot more specific to get relevant answers.

I’m not sure i understand the word “games”. Game like in video game ? Or game like in codingame puzzle ?

Before being a game-maker, you should be a game-solver first. Solve plenty of games. Learn how to solve if you’re not currently able to.