An Ol' Grumpy Gunsmith LLC / link from my personal page to my business is not outstanding.

People who have like the post on my personal FB page does not appear on my business FB page.
Cover photo requires a certain pixel size, how do I know if the picture that I want to appear is correct?
I am unable to share this FB page directly with friends. I can only share from my personal FB page. WHY?
As a new company wanting to get my services to the entire FB community what it the best and least expensive way to attract potential customers?