How do you play Bm on acoustic guitar? i tried differnt variations but cant seem to do it.?

There are a number of ways to play a Bm or any chord for that matter. I most often barre the 2nd fret and use my other fingers to play the Am chord shape up 2 frets (which is what makes it a Bm now). So that would be barre the 2nd fret, 3rd fret on the B string (middle finger), 4th fret on the G string (pinky), 4th fret on the D string (ring finger). You can also play a Bm using the Em chord shape (2nd fret D string, 2nd fret A string, all other strings open). To make that a Bm you need to move it up to the 7th fret and barre the 7th fret with your index finger fret the 9th fret on the D and A strings. If you google "Bm guitar chord" you'll find a bunch of other chord diagrams, but those are the 2 I use most often.

Ask your guitar teacher to show you - that's what he's there for.

It doesn't matter if you're playing electric or acoustic guitar, the chords are played the same. Your second description is the more common method....you're barring across the 2nd fret with your first finger and playing an Am shape with your other 3 fingers. It takes practice to get used to a full barre chord. There are simpler...but less full sounding alternative fingerings. Try this: x-x-4-4-3-2 where you play 1st string second fret, 2nd string third fret, and 3rd & 4th strings on the fourth fret. Don't strum the two lowest strings. Even if you played x-x-x-4-3-2 it would still be a Bm, just not so full sounding. Keep practicing the barre chords, life will become much easier when you master them.

It doesn't matter if you're playing electric or acoustic guitar, the chords are played the same. Your second description is the more common method....you're barring across the 2nd fret with your first finger and playing an Am shape with your other 3 fingers. It takes practice to get used to a full barre chord. There are simpler...but less full sounding alternative fingerings. Try this: x-x-4-4-3-2 where you play 1st string second fret, 2nd string third fret, and 3rd & 4th strings on the fourth fret. Don't strum the two lowest strings. Even if you played x-x-x-4-3-2 it would still be a Bm, just not so full sounding. Keep practicing the barre chords, life will become much easier when you master them.

Ask your guitar teacher to show you - that's what he's there for.