I purchased an old 10 speed 'Free Spirit' bicycle at a rummage sale at the beginning of this year. I had to replace the brake cable that ran to the rear brake since it broke, and I anticipate that I will need new tires soon due to them being really dry/cracking, but for now the bike gets me from point A to point B

I was wondering if anyone can tell me anything about the bike (I read online that it is from Sears, but that is about it)

The bike has a cottered crank, which is somewhat annoying since one of them is slightly ahead of the other, but it is manageable. A mechanic at the local bike shop said it isn't worth replacing a crank, but I may do it if I can get one off a bike that someone is trashing. I try not to jump curbs, and don't abuse the bike so the rest is okay.

Today one of my pedals broke, I am planning to replace them, as well as the handle/brake levers (rusty)

Any other tips for keeping an old bike running well?

Thanks