You know C, of course. Perfectly understandable. It is in the air that surrounds us, now, and you would be innocent to think it has always been so. To begin your exploration of the Macintosh it would be best to start on some familiar ground. Retrieve the installation disks for THINK C 5.0 from the Macintosh Repository
(From: https://beyondloom.com/blog/thinkc.html)
Here’s a fun, quick introduction to setting up a THINK C environment in Mini vMac.