Trending @Cognizant; What formalities you have to follow on LWD?

29th July is my last day in CTS but for some reasons I am going to submit my laptop on 25th.

I have approval from my PM and HCM. But I am not sure what all things I need to follow.

My HCM said I should ask to the HR, but I am not getting prompt response from them.

After I complete my formalities on 25th I don't want to return to office again on my actual LWD.

What is the process for receiving the experience letter, relieving letter, FNF and anything that I need but not knowing?

Plesse help me out so that I can plan accordingly!