Need information on Car Tyres

Already touched 57000 KM on my car and it is time to change the tyres!!!

Just when I was thinking about it, I came across tyres section in PayTM!!!

Now I need some details/information before going with online purchase!!!

Is it safe to buy online?
Just want to make sure if I’ll be getting genuine tyres and it is not duplicate or retreaded one!!

How to check genuinity?

How should I confirm if they are genuine first hand tyres!!! Will I get any quality certificate??

Is possible to negotiate with dealers with online prices??

Want to know if it possible to get online discount with dealers… Haven’t negotiated with dealers, just want to understand if someone has done it already??

Does online purchase cover warranty?

Though they claim it is warranty covered… I keep getting contradicting opinions and it is really confusing… Want to know if anyone availed warranty for any online purchase!!

Can I buy online and get it attached/fitted on the car by a dealer?

Will dealers get the tyre fitted to the car even if I purchase online..

What is the difference between 88T, 88H & 88S?

When I searched I found that my car needs 165/80 R14 tyres… But still I see 88T, 88H & 88S sub-classifications… I want to know the difference between those sub-classifications!!!