Example on the turn you check and villain bets $3.50 into 7$ pot

Your pot odds to call are 3:1
Does this mean you need to be good 1 in 4 times to call the turn or does this kind of assessment best suited for the river without further betting rounds ?Say on the turn we only need to be beating his hands 1/4 times so what I have to do is discypher what he could be bluffing with versus what he’s value betting so decide if I am in fact good enough to call profitably..I’m trying to also figure out bluffing ranges so I can make correct calls with the value to bluff ratio but I’m trying to tie it all together here.