Woah there newbie, you are indeed green. Here's some free knowledge that should get you started.
Lesson 1 - Most people who would give you advice have a motive to make you buy what they are selling, so don't trust anyone unless you know what and how they are trading themselves and want to emulate.
Lesson 2 - There are always smarter people than you, so get to know them. If you can't find anyone smarter than you, then you are not looking hard enough.
Lesson 3 - Diversify (don't put all your eggs in 1 basket)
Lesson 4 - A market cap = the theoretical amount that all the coins or shares in existance of that company (or coin) could be sold for if there were a buyer willing to pay asking price for all the shares.
That should get you started. Good luck my friend.
thank you very much