Is TCS still providing onsite in any project. It seems none project is approving onsite to anyone.

it depends on technology, your skill set and ho lw critical resource you are for the project. And on top of that what relations you have with your Project Manager also key people from clients. If you have all these, you can ask, if they don't provide then resign. But make sure you create such dependencies pn yourself that the project won't sustain without you. Then you might get it during retention.