I had an argument with my supervisor
She brought in the HR manager
After a few more minutes of arguing, they sent me home for 3 days in PAID administrative leave
I was told to return at 8+30 sharp Thursday morning

Do I have a right to know what type of meeting this is to be?

Depends on what country you live and if you are in a union or not. Or if you have an ironclad labor contract that's in effect.

Odds are you are what is called an "AT WILL" employee... and they can terminate you for no reason at all. In the USA you really have few rights to a job... outside of what normal labor laws specify or that fall under EEOC guidelines.

Arguing with a supervisor is usually known as insubordination and most employers would consider a fireable offense. Unless you can come up with a really,REALLY good reason for it. And by that I mean what THEY will see as a good reason... not just what you think is.

If all you got was paid time off...consider yourself extremely lucky.

I don't understand the question. Are you referring to the meeting you just had? Sounds like you are just to report to work after the suspension.

Also it sounds like you are getting the best of it. You get 3 days paid leave, the company loses your services for that time.

Your question really isn't clear. Sounds like you had a meeting with HR, they sent you home for 3 days paid leave, and told you to return on Thursday. Did they mention another meeting on Thursday? That's what you're making it sound like. Is that the case? Because to me it sounds like you already had a meeting, you got lucky and didn't get fired, and you're to return to work on Thursday.

Do I have a right to know what type of meeting this is to be?

You will be notified when it happens and your rights if you have any will be explained then also.