So i'm looking for a character penpal. Basically that means you write letters to each other in character, for instance we could both be wizards from the same college writing about findings or we where in an adventuring party and we are staying in touch even though the group split. You do need to be able to write English very well but other then that there isnt a whole lot involved other then pen and paper and a stamp. Please message me for more info and you can include if you already have a character in mind.

I'm assuming no luck on this :). My main concern is combat. If someone ever reads this how could you perform combat through mail?

Just as a note - the OP is asking for physical letters, not digital messages. So, as a PSA, in case it's needed:

NEVER GIVE YOUR ADDRESS TO
STRANGERS ON THE INTERNET

There is no reason, whatsoever, to send such letters physically. There are multiple ways to send digital letters be it a Private Message on this site, a message on a chat service like Discord, a shared Google Doc, and more. If anyone needs something tangible they can just print it as needed. There's even fonts designed to mimic handwriting. 

Physical addresses and even email addresses should not be given out - there is no need to.