You’re smart to look into it. While you wait on pros, try opening basement windows when possible and seal any visible cracks. It won’t fix everything, but it can help a little short term.
If your radon levels are only slightly elevated and you're handy, DIY may be feasible. But for levels above 4.0 pCi/L, or if you want peace of mind, resale value, or system certification, hiring a professional is often the better long-term choice.