All of these questions and more can already be found by searching (either this forum or google.. or use a domain specific advanced search through google for /r/sysadmin ).
I suggest you to start there and this isn't me being an asshole. This is legitimate advice; being self-reliant is basically the job description.
You caught me on a good day at lunch so I wrote an essay (partially to distract myself) but you likely won't get many other responses.
1. The best route is one you start now. It doesn't honestly matter and everyone will tell you mileage will vary. Degree with no experience (masters or otherwise) probably won't get you far and seems like an unnecessary risk to waste money/time.
You want to invest in something? Buy a decent desktop rig or two and turn it into a homelab. Download and build everything yourself, at home, and be "creative" with how you do it. Think "how would I match this business need" or go through web forums looking for problems to solve for other people/replicate on your machine using others solutions.
If you are deadset on certs/degrees it depends on what you want to do. Microsoft certs are a place to start, rhcsa etc for linux (maybe linux+ or a free online course like at edX if you're a total noob), Sec+ or OSCP for security, CCNA or Net+ is always just good to have (honestly just do CCNA), A+ is pretty worthless (most comptia stuff is anymore).
I can't say for sure but you are unlikely to just cert/degree up and then get an admin job without troubleshooting experience. Think of how a T2 helpdesk kid 2 years our of college already has a foot up on you if they've been certin', homelabbin', and working the trenches at an MSP.
2.Illegal sites or, if you have a .edu email account, check out Dreamspark for free MS OS. Most products (like esxi/vmware) have trials or free versions to get your feet wet.
3.Keep things in writing, keep multiple copies, and make sure you enjoy technology. Expect to never stop learning as technology constantly advances. Remember this is a SERVICE INDUSTRY and customer service is a big part of that; not only that but a good deal of businesses look at IT as a cost center so expect political battles.
Notable books: Network Warrior, Practice of System Administration, Time Management for system administrators.
And, on a final note - stop expecting people to hold your hand. None of this information is particularly hard for you to find with a 15 minute google search of this subreddit or strolling through the wiki.
Good luck.