Hey Nikita,
Best hostel in Jodhpur is Zostel as I had stayed there in January. It is located very to near clock tower and at a walking distance from Toorji ka Jhalra. Mehrangarh fort can be seen from the rooftop of zostel. Ranisar & Padamsar lakes are nearby, if you walk then it would take 10-15 mins, or you could take an auto rickshaw.