I like to get the tracks to sound pretty good before I start editing them.
First, remove noise. Let's work on the first track. Press the S box to listen to that track in solo mode—that track, and that track only.
Then, find a section of that track with where the person isn't speaking. Ideally, where the only thing you hear is the background noise (but a few breathing sounds won't be the end of the world). When you find it, select and drag a portion of the timeline to make it yellow. When the timeline has a yellow strip, you're in cycle mode—and when you hit play, it will loop that section.
Make sure the circled i button is set, so that the following panel is visible. There is an area where Audio FX go (such as EQ, denoise, flangers, etc.), and we're about to starting adding Audio FX. The left column is for Audio FX that are applied to a specific track, so we're going to focus on that for now. (The right column, next to it, has Audio FX that are applied to the output track—but we'll get to that in a bit.)
You'll want to add an Audio FX, Audio Units > Acon Ditigal > Acon Digital DeNoise > Mono (or Stereo or whatever). Let it "learn" the section that's just background noise, then "freeze" that noise profile. Oh look, here's a video!
Second, remove reverb. Or, you know, calm it down. Our podcasts are often made in echoey rooms. By far, the best thing to do is to get clean, non-echoey sounds in the first place (record surrounded by blankets and books!). But keeping reverb under control can still make a better product.
Again, add an Audio FX: Audio Units > Acon Digital > Acon Digital Deverb > Mono (or Stereo or whatever. This time, loop on a section where the speaker is talking a lot (and, maybe, loudly). Set the top section to "room reverb" and tweak the settings to do as little change as possible. It's smart to check Difference Monitoring, which lets you listen to the sounds that are being removed! That way, you can turn down the various knobs until all you hear is reverby echo, rather than the main speech.
Here, another video might help explain?
After that, you might want to add a few more tweaks. Perhaps some EQ to help open the sound up, or some de-essing (if the /s/ sound is coming off too sharp) or a de-plosive plug-in (to reduce popped /p/ sounds—Acon doesn't include one, but Izotope does). But perhaps this is enough.
What you want to add next is Compression, which deserves its own post.