Step 1: Download Putty Client Software from below link as per your system compatibility.
Step 2: Enter IP Address and select connection type ssh with port 22.
 

Step 3: Enter Username in auto-login section; it will save your time by not entering username each and everything while taking access.  

Step 4: Upload your SSH-Key Path in Auth tab

Step 5: Save the Session after configured all things from this are not required to do above Steps 1-4.

 

Step 6: Double Click the saved session and you are connected to server.