I got 15000 Upsee rank. What are the top colleges for me to do B.Tech with mechanical or CS?

Based on your rank you can get ME branch in certain government Colleges. These are the government Colleges where you can apply are:

1. Chhatrapati Shahu Ji Maharaj University Kanpur

2. Lucknow University

3. Bundelkhand University Jhansi

4. Rajkiya Engineering College Sohnbhadra

5. Rajkiya Engineering College Kannauj

These are the government Colleges where you can get admission based on your rank. If you want to take admission in CSE branch then you can apply for these private Colleges:

1. Inderprastha Engineering College Ghaziabad

2. Krishna Engineering College Ghaziabad

3. GL Bajaj Greater Noida

4. ITS Greater Noida

5. Sharda University Greater Noida

6. IIMT Greater Noida

These are the private Colleges where you can get CSE BRANCH.  It also depends on the cutoff list. As it vary from year to year . It also depends on the number of students appeared in the exam and the level of paper. So go through the counselling properly. Give your preference according to your  rank .