Spent 45 years writing software, some of it for really cool projects (camera controller for a Mars orbiter)
Welcome to the forum.I bought a collet set and a clamping set with the mill. Other than that I'm good, at least for the moment. My Dad left me vises, end mills, reamers, taps, lathe cutting tools (up the ying-yang), v-blocks, parallels, calipers, micrometers, dial indicators, etc., etc., etc. I won't know everything that I have until I get it all laid out and sorted. I have a 6 drawer tool box, on top of a 4 drawer stand, sitting next to a 5-6 shelf 18"x48" shelving unit, all loaded with something to do with metal working.
If you figure all of that out, write a book and I'll buy the first copy!!Another thing is planning the sequence of cuts to reduce the steps and give you a usable part rather than another learning opportunity.
I am having quite a few learning opportunities still and find it frustrating to mess up after the 2nd or 3rd go round but I know it will come with time.
Good luck.
David