A 2000 FIDE player will sometimes beat a low level professional player. Just like I sometimes beat players who are 200 points above me.
It's impossible to give you a number that will be equivalent to 2000 FIDE and that works for every person. I've heard that standard is a bit inflated so I'd say at least 2100 standard before you can start to guess that you're close to 2000 FIDE...
But if you've never had an established FIDE (or national) rating, then it's even more of a wild guess because with no tourney experience you're going to need some games to get adjusted to tournament play. It's like asking if my blitz rating is ______ then what's my standard rating even though I've never played standard.
I had 3-4 people at a club (we played G/15 sometimes with 5 second delay) tell me I was 1800-2000 USCF strength... I somehow doubted it and when I started to play in tournaments I found out they were about 200 points off. You really can't know unless you go play FIDE events.
What is the approximate FIDE rating will a 2000-rating live chess player (standard) have? Can he beat low level professional players?