How to tackle the 90 days notice period outside. And how we can reduce that notice period inside tcs

When I am applying for a company I get regret mail due to the 90 day notice period of Cognizant. How are you folks dealing with it ?

TCS gave me a system admin role as a fresher. It's extremely boring, same kind of work everyday. How do I switch to another company keeping in mind the 90 day notice period and my current job role?

I have a question: What is the notice period in TCS for an associate? Is the notice period different for someone on the bench?