I want to work in tor messenger and want to know what all I have to do to get in the flow of the work. Any help would be very helpful.

Thanks for you interest.

Here're the docs on building Tor Messenger, https://gitweb.torproject.org/tor-messenger-build.git/tree/README

And, here's for Instantbird on its own, https://developer.mozilla.org/en-US/docs/Mozilla/Developer_guide/Build_Instr... to which you can add the OTR extension, https://github.com/arlolra/ctypes-otr#dev-env

We have a number of open issues, https://trac.torproject.org/projects/tor/wiki/doc/TorMessenger#Tickets https://github.com/arlolra/ctypes-otr/issues

Other than that, there isn't really any procedural stuff. Just find something that interests.