Help with Contacts & Account Records

I am trying to link my contacts to my accounts. My previous assistant set up everything in contacts. I have since moved all my clients to the accounts tab but I am unable to email out of that tab I have to go look them up in the contacts list.

I know leads you can email from the quick action - how do I move a contact to an account so that I can send email from that area and not have to go back and forth?

Help.

Thank you.