Can I use the same SOP for all universities for which I apply to or I need to draft different SOP?
Basically, the SOP or Statement of Purpose, which mentions your study plans will only change based on the subject you are applying to. In case you are applying to different universities, most of SOP content would be same barring the university details which would be different.
If you are applying for different subjects or specializations, you will require to change you SOP according to those requirements.
SOPs describe your academic background and strengths. A good SOP should be fit with the university as well as the program you are applying for.
Ideally you should write a separate SOP for each program you apply for so that it is fit with the university and indicate that you know about and are interested in that specific program. But you might not have time to write so many SOPs and the major part is same in SOP, so you can take time and write one good SOP and then change the particular part of SOP according to the program you apply for different universities.