OK that makes it pretty easy. The races are shot, so you need a new headset.

If you have a quill stem, odds favor a 1" headset. To confirm, measure the outside diameter of the stem, and the fork is 1/8" larger. Then search for a ISO 1" threaded headset (there are plenty to choose from).

Tou'll need some tools (some of which can be improvised) to remove the old one, especially the crown race on the fork. Then other tools (which can be improvised) to install the new one.

This isn't difficult, but the tools can add considerably, so the best bet may be a bike co-op if there's one near you. That way you can get access to tools and guidance all at a nominal cost.

Otherwise, plenty of tutorials available on replacing headsets.