kind replies

Yes Gary, you can answer them like that and may add you are perfect at the end of the sentence..

Yes, but you can also reply in this way: "That's very kind of you".

Or you can say "I'm sending you a case of beer as thank you gift"

A bunch of flowers will do

The sentence is fine.

Not only a case of beer or a bunch of flowers, you can expect a lot from me. But all these after a few days because now I am a student under the control of my parents, and also I don't know the procedures to send across you these things.

But I am sure one day I will do after I start doing job.
Please believe me.

Please let me know if you believe me or not.

You don't have to send us any presents Gary. We do this for fun.

Your English has improved a lot, well done.

Oh yes, Gary, I was only kidding! I'm sorry you thought we truly expected anything from you.

It's nice to hear that we're helping someone, and that's all we really want.

So I don't get any beer?

Clive

Clive, I promise to send you half of all that I receive

Remembering your early attempts, this is a remarkable post. Your English has improved amazingly well. Keep going!