I bought the frame off craigslist for $50. I knew it had the one dent but figured it would be safe to ride. Anyways, I found a second on the downtube and started to wonder. Both dents are isolated, meaning there isn't another dent on the other side of the tube. Does anyone know about these things. Its steel btw.

I'm right around 250lbs and I've ridden many frames with similar or worse dents without issue, and I am far from easy on frames. No 5 or less stair set is safe from being jumped down. I'd ride it and feel perfectly safe given that it's steel

Steel can be pretty resilient.

Those are not the typical bends from a front end impact, so you are safe there.

Top Tube bends about a foot back from the head tube are often caused by the handlebars, either in a crash, or perhaps even bad packing.

Anyway, just put some wheels on it and go out and put some more dents in the frame to match

They are fine . It steel after all . If it brother you fill in with body filler and paint . If not keep a eye on them for rust .