is it implemented using Box2d or using properties of different tiles when using a tiled map ?? also can i abandon the sprite sheet idea and make animation of game character using Libgdx ??? also if you can post some tutorials that would be great 
I am kinda new to LibGDX, but i believe that Box2D does the collisions. I have been using foriegnguymike’s youtube tutorials, and the way i saw him do it was using Tiled for making tilemap then using Box2D put fixtures around the tiles for collision detection.