Is selling a book on a case basis easy on Shopify?

I am trying to decide if Shopify is right for my dad and I. My father wrote a book that we are wanting to sell by the case to market centers.

How easy has it been to sell on Shopify?

Do you need a sales tax permit?

How have you as a seller dealt with Shopify not remitting your taxes?

I think how to deal with sales tax has been our biggest question.

Also what is Shopify’s take away from sales?