I am new in this field, and I need help! How to put AutoCAD file in to MasterCAM 9 so I can make a toolpath? I tried many times, and I made it only with 2D drawing, not with 3D. Who knows how to do it... I would be greatfull.

I have found DXF converts to 2D.
IGES has converted with 3d intact, give it a try.

If your AutoCAD file only has lines, arcs, etc, then export as DXF

If you have solids and/or surfaces, try using STP ( this can be imported into Mcam and then get your wireframe geometry from it ( create curves on 1 edge, or all edges )

IGES will work, but it may be awkward getting user-friendly from it as it comes in as a tessallated mesh ( triangles )

if creating geometry from surfaces, you will double-up on curves ( best to get them from the solid )

PS-- there is also a Mastercam forum here for further info/searches