Yes, the gear you find will have randomised stats within a certain value range that is based on its item level or gear score. The higher the level, the better the stats.

When upgrading the Tech Wing in the Base of Operations, there's a perk that provides you with a "Recalibration Station" where you can re-roll a chosen stat (or 2 stats on "Classified" end-game gear) if you wish to improve/change something. (I think you can just fasr travel right into the Terminal hub and get it for free, but it's been a while since I had a brand new character.)

If you're still brand new to the game and in the process of levelling up to 30, then I personally wouldn't worry too much about getting a "perfect" build together.

Just experiment and throw together whatever gear you manage to loot along the way, see how balancing each of the three main stats (Firearms, Stamina, Electronics) alters your effectiveness, survivability, and so on.

When levelling up you'll go through so much random gear, it's really not worth stressing over too much.