https://www.google.com/amp/s/amp.red..._bracket_on_a/
I noticed it’s not easy looking up the bottom bracket and crank info. This link may be of some help. You need a bottom bracket tool or a special wrench you can usually pick up in any bike shop. Also if you do not have a torque wrench buy one. For cranks and B.B.’s I have a Park Tool beam-lever type. Cranks come in different lengths so make sure you buy one the same size. Nowadays most B.B.s are external bearing types vs the internal cartridge which you probably have. You should be able to find an appropriate external that works. That will give you more choices in cranks. I’m thinking you have old square taper B.B./ cranks, which you can still find.