I may have been hacked with LogMeIn.com

Hi everyone! My first post on here and I didn't see anything similar through a search. I had a moment yesterday of pure dumb and hoping my MacBook isn't hacked.

So I purchased a Brother printer, and was having problems setting it up. I googled customer support and called the number that popped up. This was not a Brother customer service rather a random number that after doing an additional search, found out to be pure spam.

A person answered the phone (I was thinking still that this was a Brother rep) they sent me to LogMeIn.com and gave me a 6 digit number so that they could see my computer screen. He clicked on "Terminal" and then clicked on "Console" and showed me that my computer is being watched by over a thousand people with malware. Then he started telling me all the things his "company" could do for me. Including deleting malware and fixing my printer problem. This is when I got weirded out and hung up. Ive kept my computer offline since then and looking for some guidance now.

Ive had my MacBook for 5 years and love it. Is there anything I can do to potentially get ahead of any security problems? Thank you everyone in advance!