Welcome!

$75 isn't a lot to invest in a bike, so I say ride it, log some miles, then upgrade or change to your heart's content. Just about anything will get you started for bike commuting. Your distance, terrain, and how much you want to go all-weather will probably take you in the direction of some upgrades (or not, as the case may be).

If the bike will fit fenders and a rear rack, those are near the top of my list for helpful commuting equipment. Same for lights. Plus, you can take the rack (probably) and quality panniers and lights if you decide to get them and put them on any other subsequent bike you decide to get down the line.

Ride safe and enjoy!!