(only the first image was available when I wrote this..)

Thats a square taper crankset, which can be removed with a standard crank puller.

Impossible from the picture to see what BB you have other than it being a square taper variety. However, probability suggests that it will be a cartridge style sealed BB unit.
Its a cartridge style BB. To replace the BB you will need to know its shell width (68 or 73 most likely)
Looks to be a 68mm shell and then the spindle length varies, which can go from 103mm or so upto 130+. You measure the axle length with the cranks already removed.

Tools:

8mm hex key to remove caps.

Chainset/crank puller - https://www.amazon.com/Skylety-Remover-Bicycle-Crankset-Maintenance/dp/B08HZ2XDD6

BB tool (most likely if sealed unit) - https://www.amazon.com/Compatible-Standard-20-Tooth-Cartridge-Octalink/dp/B0BZNR2K26

Digital calipers to measure the BB shell width (the frame tube the BB is in) and the axle length.

Typical (but not specific) replacement BB - https://www.amazon.com/SHIMANO-BB-UN300-Square-English-68x115mm/dp/B088XS9HY9

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It can be a nasty job as BB's have a tendency to get stuck in frames.If you are uncertain, pop it down to an LBS who will be able to check it all for you at a reasonable charge.

Video on how to remove a BB. - https://www.youtube.com/watch?v=yBnYoYVTnloVideo how to remove cranks - https://www.youtube.com/watch?v=cPQyQnNdews