You're lost in the woods. You come into a clearing where you find:
(i) an in-tune fretless bass player
(ii) an out-of-tune fretless bass player
(iii) Santa Claus
Q: Who do you ask for directions?
A: The out-of-tune fretless bass player. The other two are figments of your imagination.
this made me laugh... there is a reason that Leo called his first bass, which had frets, the Precision Bass.
Still, to the OP, don't be discouraged. Put your fingers on the lines (that is where the frets would be if there were any), listen, adjust if needed and you'll get there.