Here is an idea (worked for my wife when I taught her to ride), use one ride a week for teaching then the rest of the week you can practice what your bf, or who ever shows you the techniques, taught you.

1. Start off with an easy area that has some hills, learn the gears to use to keep your momentum while climbing and when to shift into them. It is a bit different in the dirt then on the road.

2. Learn to descend steep hills. Find an area with short but steep hills that can be rolled through.

3. Find an area with ruts and small roots and learn to ride over them. Do this on a flat area and not on a hill.

4. Next, find some small 6" to 12" drops and learn to ride down them.

5. Find a trail with all the above and ride it.

You should also practice track-stands, which you can also do on your road bike, and very tight turn (will help with switchbacks). But most of all practice. Last word of advice, learn to love crashing it will make the ride much more enjoyable

I will also add, I would stay away from the clipless until you get better with the obstacals