can i sell my T-shirts on Amazon Here on this Forums ?

Nope.

Self promotion is not allowed here.

And also you should consider the audience. This is a forum of garment decorators, not buyers of decorated garments

Also, 95% of the point of being on Amazon is access to Amazon's traffic. It is the largest online marketplace in the world. People go there to BUY stuff. Nothing much that you or I do can compare to that.

Ditto NoXid.

Trying to sell shirts here, even if you COULD do it-and you can't, would be like preaching to the choir.

Members/visitors here make the shirts you're trying to sell, they don't buy them.