Hello Gurus, my 1980-90s Schwinn World Sport bike's chain is rubbing the front derailleur, slightly and intermittently, and that rubbing noise is bothering me, on my bike rides. I tried to fix the rubbing noise by rotating the limit screws, unsuccessfully. Then I noticed a slight play in the crank arm, and then also noticed the bottom bracket is out by a few threads, which could be the reason for the rubbing noise.

From the below pictures, does my bottom bracket, on the drivetrain side, need to be tightened? Is that possibly the reason for the chain rubbing the front derailleur? If so, how do I tighten the bottom bracket? I do not have any special tool for the bike bottom bracket, but I do have all kinds wrenches, screw drivers, and a mechanical toolset that I use to do repairs to my car.

Thank you in advance for any advice and help. 🙏