Yep, look for an after-market video card. Check your power supply first, and the what kind of slots you have for expansion. A lot of PC only come with 300 watt or so power supply, which will limit the amount of card you can put in. But card makers make some decent cards that plug in that you won’t have to deal with upgrading power supply.
If you want a top end card you may have to upgrade your power supply.
I think Nvidia and some of the other top card makers have little utilities you can download from their sites to see what kind of card expansion options you have.
You can get a decent card and performance boost for $50-100. If you want real top end it can get quite expensive in a hurry.