Hey Aspirant ,

Staff selection commission is a government organization responsible for selecting deserving candidates for various government posts.  There are two sorts of exams conducted by SSC , one is CGL, combined graduate level and the other is CHSL , combined higher secondary level examination
It is split into three phases
1 .preliminary -tier 1
2. Mains - tier 2
3. Descriptive test - tier 3

Hope this helps , all the very best !