Well you want to start by studying these forums, and learning the correct place to post your questions — it seems to me that what you have primarily is a programming question, not a game design question. The Getting Started forum would be more appropriate.
Once there, don’t just post (and read responses to) your own questions; read all the posts, and the answers. You won’t understand it all, but you’ll gradually pick up more and more, including pointers to great tutorials you should go through.
Next, yeah, actually work through the tutorials. If you’ve never touched Unity, and never made a game in anything else either, then forget (for now) about making the RTS game you really care about. Your first goal should be to get a sprite on the screen. When you can find the Play button, and clicking it causes some sprite to appear in the game view, then that’s a victory! Have a little celebration.
Then sit back down and learn how to make the sprite move, at a continuous speed in a straight line.
And so forth. Take it step by step. I don’t think you would say “Hey Dad, I just bought a circular saw; I’m going to go build a 3000-square-foot house in the back yard, with all the plumbing and electrical and everything up to code!” The very notion is ridiculous, right? Before you can build a house, you need to collect tools and (most importantly) build a LOT of skills. The professionally-built houses you see are built by teams of specialists: plumbers, electricians, carpenters, roofers, etc., and to learn to do all that yourself will take years.
Software is the same way, only more so, because a modern software app is among the most complex (in terms of number of unique pieces) artifacts ever created by humans. The professionally-built games you see are built by teams of specialists: programmers, designers, artists, directors, audio engineers, etc. To learn to do all that yourself will take years.
But don’t despair! All that is incredibly fun and rewarding. And, just like in learning carpentry, you can do a lot of cool stuff along the way.
But your focus for the next year or two should be on learning to use your tools, and build the skills you’ll need to someday create the game you have in your head.
Good luck!