I want to take admission in UK top 100 university in msc management and my English score 86 in 12 CBSE so my ilets exam should be waived off?

Yes, ofcourse. IELTS is just a language proficiency test and not the benchmark to study abroad. UK is one of the most popular destinations to study without UK. Here is a list of the top b-schools that do not require an IELTS score in UK:

1. King's College London

2. University of Bath

3. University of Manchester

4. Cardiff University

5. University of Liverpool

6. Lancaster University

7. University of Strathclyde

8. University of Birmingham

9. University of East Anglia

10. Newcastle University London

If you had English as your core subject till class 12th and you scored an easy 75%, and even your mode of study in bachelor is English itself, then you can be waived off from a language test. Since you mentioned your score is 86% you can easily get into any of these universities. 

Let me know if you need any further information or help with applying to any of these universities.