Hi aspirant on behalf of the general rank you have got i.e. 21201 in JEE Mains exam below are the colleges in which you can get in for admission in CSE branch;

• NIT, Meghalaya
• NIT, Agartala
• NIT, Srinagar
• NIT, Imphal
• Jiwaji University, Gwalior
• Pondicherry Engineering College, Pondicherry
• Gurukula Kangri Vishwavidyalaya, Haridwar
• Shri Mata Vaishno Devi University, Katra
• NIT, South Goa
• Hemwati Nandan Bahuguna Garhwal University, Garhwal
• Assam University, Silchar

Etc.

For predicting more colleges I would like you to refer you college predictor tool by careers360(link mentioned below);

https://engineering.careers360.com/jee-main-college-predictor?icn=QnA&ici=qna_answer

Good Luck.