theawesomerain Did you remove the mods by exiting the game then moving the whole Mods folder to your desktop, then remove the localthumbcache.package file, then try re-opening the game (without re-adding any Mods or CC) and entering a brand new save top see if it opens then? If it doesn't open then I would recommend checking if any of your mods save settings in other locations (outside the Mods folder), and if they do remove those from the game also to test. After you're sure you have removed all Mods/CC, and the mentioned cache file, you could also run a game repair. Let the game repair complete before re-opening your game and trying again to open a brand new save.
There are some excellent tips and guides on this process in teh Mods & CC area: https://forums.ea.com/category/the-sims-4-en/discussions/the-sims-4-mods-and-custom-content-en