Is there a way to create my own puzzles or game situations using the analysis board?

I would like to create different situations to try to develop solutions. Is there a way to do this?

Yes, you can create your own puzzles or game situations and then make a study of them. You can either check if there are puzzles from your games (https://lichess.org/training/of-player?name=jmsthurber) or you can just analyze your games and find tactics that you (or the opponent) did or missed. You can click the 'Learn from your Mistakes' and check if you missed any tactics. You can also learn from the opponent's mistakes and find tactics and combine them in a study. You can then create game situations as you like and then add them to your study.