Welcome to the Guild!
The two best ways to learn on this site is to post whatever your current maps look like. Best to post something that you're currently working on, then ask for critiques. We'll do that, but point out to different techniques using whatever software you're working with. We've got lots of gurus on different apps - not all software, mind you, but offering suggestions that should still help.
Once you're comfortable using different techniques to create elements of a given map, then participating in the monthly challenges is the best way to learn. Because of the deadline (usually only 25 days with the remaining for final submission and voting.) We've got a lite version, so the newbies, like yourself have a better chance at winning. (Usually, no prize, just an ego thing and a badge under your name.)
I've learned more on making better maps by participating in the challenges, than anything else on this site.
Still check out the tutorials, follow through step by step, ask questions when you are stuck, and the author or other contributor will guide you to success.
Explore the site, there's lots to learn - and do the tutorials, start posting maps (no matter how lame you think they are) as they might have great potential, and when you think you're ready jump into the challenges!
That's my advice, again welcome!