Hello aspirant

For jee mains there are several counsellings held at different levels (state level , national level)

JOSSA and CSAB are national level counselling which tells you about the seat matrix of IITs , NITs and IIITs of all over india. Apart from these counselling there are other state level counselling . for ex:-

JAC Delhi (for Delhi)

JAC Chandigarh (for colleges in Chandigarh)

HSTES (for Haryana)

GGSIPU (for colleges under indraprastha university , Delhi)

and many more....for different states

i hope my ans helps.