Wow, what a welcome to R2R!
I think you've seen the links to youtube videos that can help. And some instructions as well. ihavecrabs is 100% right about the T247B not being the most intuitive system ever made. LOL! I used to work for Ocean Revive and you should have seen the first prototype's instructions! I took me over 2 hours to figure them out.
If you are still having issues with the timer, I'd be happy to try and help you through it. So what exactly is it that you are having trouble with (other than everything!). LOL.
BTW, the T247B is a well made fixture. They just tried to put too much control into a small brain with only a couple of control knobs. Take your time and don't get frustrated. Even I had to walk away from mine a time or two when I was changing the schedule!