In terms of tasks MSP can cope with, I regularly produce programmes with 600-1200 tasks. The largest was about 5-6000 tasks, with an addition near the end of around 1200 snags (so 6-7000 tasks in all), and it handled it fine. So yes, project can deal with large programmes

For your example, I would suggest that using 1 programme would be simplest. Each individual project can be added under its own summary bar, and would remove the need for task resourcing at a deeper level.

I would also go with Julies suggestion of finding a good course. I was self taught and it was a struggle for the first few years, although it does mean you have a good understanding of what you are doing.
Don't go for a generla planning course- these tend to be for project managers (allegedly) and dont have enough detail to make them worth the effort. Best case is to find a planner that can spare the time, and get a quick run through of the basics, then return when you find yourself out of your depth. there is no substitute for experience; MS Project is not simple, and someone showing you what to do is worth its weight.