colej67 While $300 or less is technically doable, there's a significant improvement in the hardware you can find for more like $350-400. I can look for used options closer to $300 if you want—just let me know—but I'll mostly list the better ones that are a bit more expensive for now since it sounds like you're willing to go higher for a worthwhile upgrade.
This is the best $300 laptop I'm seeing though, capable of running Sims 4, all current packs included, on medium graphics settings:
https://www.walmart.com/ip/5096127174
This one is a lot faster, something approaching twice as fast in gaming, meaning you would probably be able to play on high graphics settings:
https://www.walmart.com/ip/5144605602
The graphics chip in these is even faster than that, in the 20-30% range, but they're both $400:
https://www.bestbuy.com/site/dell-inspiron-14-2-in-1-14-ips-led-fhd-touch-screen-laptop-amd-ryzen-5-with-8gb-memory-512gb-ssd-midnight-blue/6576719.p?skuId=6576719
https://www.newegg.com/p/N82E16834360373
None of these laptops have 16 GB memory, which would be nice to have but is not strictly necessary for Sims 4 alone. If you do want 16 GB RAM rather than 8, the cheapest option I saw that also had hardware at least as good as anything on this list was this one, for $433:
https://www.walmart.com/ip/5262667268
In terms of performance, it slots in between the first two laptops listed above and should run Sims 4 on medium-high graphics settings. So this is a question of your highest priority: running Sims 4 as well as possible, or being able to multitask.
There aren't a lot of good options out there at the moment, at least as far as I can see, but these are about as good as I'd normally find; it's just that there are fewer suitable laptops than normal. However, if none of these is what you want, let me know why, and I can try to find something more to your liking.