Changing the crankshaft pulley is not the first job a diy mechanic should attempt , unless you buy a manual , read and understand the instructions in the manual,have all the tools required and know someone who can do it for you ,should your attempt go wrong.
Pay someone else to do this for you. If you want to learn ask if you can watch how it's done.
Doing your own fluid level checks , then oil and filter changes is a much better place to start learning.