There are a couple options for a Windows-based OpenSSH daemon that are free. The top two that I prefer are freeSSHd and widely popular OpenSSH with Cygwin.
My top pick probably goes to freeSSHd because of it’s simplicity and quickness to get setup and going.
Cygwin + OpenSSH
There are TONS of tutorials on how to setup OpenSSH/Cygwin SSH daemon on windows, here are a few more recent:
Choosing an SSH Client
Once you choose your SSH daemon (server), you will want a client to work with.
I can’t recommend PuTTY enough!
You can also find alternatives and hacks for PuTTY which offer newer features. A good one is KiTTY. Below is a screenshot of right-click new features for KiTTY: