In Georgia, it’s fine if you produce your own tea from dried herbs (you can dry them yourself), and it’s also okay if you start with commercial bulk tea as a base. If you’re just reselling commercial tea in smaller amounts (reselling individual unopened packets), you may not need to register as a cottage food operation. You can ask your ag dept if something like a seller’s permit would be better for you.
If you repackage the exact product and slap your own label on it, this may be illegal, depending on if the original product is copyrighted, patented, or trademarked. Even if it isn’t, if your business got big enough it could be considered unfair competition. I wouldn’t advise it, and it’s better to significantly change the product or create your own from its ingredients.
You may not provide prepared samples of the product with a cottage food license. You should call the ag dept and see what requirements there are to sell hot tea or coffee at a market. You may not need a full commercial license for that.