Kashering non kosher Jewish kitchen

Do used non kosher pans pots silverware need to be labeled before tovelled or vice versa? Do oven grates or grates on top of burners need toveling?
Are there any things that can’t be kashered or don’t need to be kashered/tovelled in a situation like this?

Do used non kosher pans pots silverware need to be labeled before tovelled or vice versa?

I am not understanding. What type of label?

Do oven grates or grates on top of burners need toveling?

The grates in oven - if you will ever put food straight on the grates - bread, reheated pizza etc, then yes.

Grates on top - No.