I am making a game and I don't know what it should be about

I am making a game and I don't know what it should be about. I have somewhat of an idea about what it should be about. Like I want it to be about a sanctum that is in ruins that a YouTuber (you) goes to the sanctum with a few others because of the rumors that surround the sanctum and something happens while the YouTuber and their friends are there. However, I don't know what the rumors are going to be and I don't know what the name of the sanctum will be. Also, I don't know what will happen while they are there and I don't know what will happen after they leave the sanctum. Plus, I don't know where the sanctum will be. I do know that the sanctum has to be at least 1000 years old or older, it has to have been abandoned at least 100 years ago and abandoned at a maximum of 800 years ago. Also, the reason that the sanctum was abandoned must be unclear and mystical. Also, the sanctum must have somewhat of a horrifying past and it has to look like it was abandoned 10 to 40 years ago. The name of the game is Mystical Sanctum Ruins. I am also looking for people to help me make the game itself, but my biggest priority is getting ideas for the game. So if you want you can ask me to let you help with the code part. Also, if you do ask me to let you help with the code part, there is a very high chance that I will let you help. Just saying I will give you credit for helping me, even if you just gave me ideas for the game, I will still give you credit for at least giving something to the production of the game. The game will not be making money, so if you do decide to help with the coding part, then don't expect to be paid because you will not be paid, you will just receive credit for helping. Also, I don't know how long it will take to make the game, but when the game is ready to be released, the first ones to know about its release will be all who have received credit for helping. Also, when the game comes out, the game will be free to play and a single-player game.