Selling Online Q&A

In my experience this can easily be linked to a payment platform using the URL pasted into Facebook - for it to look great I’d use a landing page software such as Leadpages 

Just as there are a huge number of mistakes starting a company, there are many mistakes starting one online as well.

In fact, your question is too generic. Perhaps explain a little about what your business is aiming to do and you'll get some answers.