@Talexa99 Unfortunately, your laptop is mostly not upgradable. Its processor and the graphics chip integrated into it are both quite weak for the game, and neither can be replaced without a lot of trouble, and given how these laptops are built, probably either not at all or only at a cost that's above the value of the laptop.
One thing you could do is add another 4 GB memory. While that wouldn't make Sims 4 run well, it would likely help somewhat, and RAM is pretty cheap. You'd need to check the manual for your laptop, but it looks like this would match, and it's $28 for a second 4 GB stick:
https://www.crucial.com/compatible-upgrade-for/dell/inspiron-15-(3531)
You could also likely buy through Dell.
However, the processor and graphics chip are still going to hold back performance to a significant extent. I'm sorry to say it, but there really isn't anything you can do to play on more than low settings.
