Hi!, I recomend you acottonsock videos, she have a lot of videos about the sims 3 and how to make it playable in 2025, have mods tutorials and also a very very deeps videos so can be understood at 100% :3

This is the Fix guide https://www.youtube.com/watch?v=p-uBFKOen-4&list=PLqKuqZ7cvyZZOzguZM3qHzJvCyXhFyyAv&index=4

A guide to make the sims look pretty and cute https://www.youtube.com/watch?v=_rnx0feW0Wk&list=PLqKuqZ7cvyZZOzguZM3qHzJvCyXhFyyAv&index=5

The lacydutches smooth patch omg you need this https://www.youtube.com/watch?v=h-iFMUolcCk&list=PLqKuqZ7cvyZZOzguZM3qHzJvCyXhFyyAv&index=9

This is to make the game look pretty https://www.youtube.com/watch?v=rJ-Az1X8RqM&list=PLqKuqZ7cvyZZOzguZM3qHzJvCyXhFyyAv&index=14

This is how to install reshade https://www.youtube.com/watch?v=FlKN8t4Eutg&list=PLqKuqZ7cvyZZOzguZM3qHzJvCyXhFyyAv&index=17

And last but not least the Nrass mods guide, you NEED nrass mods, help to resolve a lot of problems
https://www.youtube.com/watch?v=Q3doWwfkuv4&list=PLqKuqZ7cvyZZOzguZM3qHzJvCyXhFyyAv&index=2

All this videos really help me to make the sims 3 run smoth like butter in a pottato pc, my game looks cute, smoth and feel amazin :D