What I was going for was to appease some of your worries/preconceptions and to emphasise ways in which you can enjoy VR without fear.
So, start small. (yeah, facebook and all that, but you’re really not their target audience 
) Get a rift S or a Quest, play the hundreds of free vr games to get the hang of it (a lot of games are less intense as a flight or a racing sim), and by the time you get it, you’re all set to upgrade your pc and get into serious VR simming.
As is right now, your PC is able to run some simple VR games. That should be enough to get you hooked and better understand how it all fits together.
I might have misspoken. If you have trouble maintaining your balance in real life, you may actually have less problems (with nausea) in VR (but do it sitting down. It’s no shame and in no way does it take any fun out of it. and it’s 100% safe)
I follow this guy on youtube https://www.youtube.com/channel/UCSVjrpufOzTd3jZsUGs-L0g
he reviews a lot of (free) VR games and you can get an idea of what VR looks like in different situations as he films himself as well as the VR feed.