TheLordeSimmer Try uninstalling and reinstalling your VC++ 2022 runtimes, which shouldn't have anything to do with Sims 3 but is often related to installation failures in general. Open Windows Settings > Apps, scroll down to the Microsoft Visual C++ Redistributables, and uninstall everything from 2015 and newer. Don't touch the older versions.
You can get new versions of the 2022 runtimes here:
https://learn.microsoft.com/en-us/cpp/windows/latest-supported-vc-redist?view=msvc-170
You'll need both the x86 and x64 versions, but you can skip the ARM version. Restart after installing and before trying to download Sims 3 again. I would suggest downloading only the base game at first; you can deselect the packs you own, and come back later for those.
If this doesn't help, please do the same as above for the 2005 x86 runtime, the one Sims 3 actually uses. The installed version won't say x86, but unless it says x64, it's the right version. You can get a new copy here:
https://www.microsoft.com/en-us/download/details.aspx?id=26347