You're recording at too low a level and/or your recording equipment isn't good enough.
Usually careful EQ-ing and noise gate (both stock in Studio One) can help, but it's crucial to get the source recording right.
Lastly, there's free plugin from makers of Reaper that you can teach how your noise sounds and it will "subtract" it from the audio, but I've no idea how well it works. It's ReaFIR here:
https://www.reaper.fm/reaplugs/