If I understand what you're asking correctly, there is a way to do this. Instead of sharing to the gallery, just save your Sim/Family/Lot to your library instead of the gallery. I have attached screenshots to include what I mean.
thanks for trying to help, but if the game is uninstalled or something happens to my pc, i would lose my creation because it's not connected to the internet
I don't think that's the case. I can access those files even when I play the game offline. That being said, if you lost access to your actual account, then yes you would lose access to those files. If you're looking for a way to save and backup the files without being tied to your account, then you would have to save and backup your Sims tray folder like the previous commenter mentioned. Even having a "private gallery" wouldn't resolve that because if you had to create and use a new account, you wouldn't have access to that private gallery anymore anyway.
i would not like a private gallery in case i lose access to my account, i want to save/upload it for myself, that i can access even if i change computers, even if my computer breaks down or even if the game is uninstalled
if i have a private gallery inside the game, every time i install the game and link to my account everything i created would be there
