You mean from “normal” to touch display? I cannot comment on a touch device…
When you remove the back cover, it is important that the adhesive tape remains on the cover, not on the old display. In case your adhesive does not work anymore, you should clean the back panel properly and install new adhesive
Here too many screws are removed. Only the 4 denoted with a circled "1" have to be removed.
This step is not necessary. The screws do not have to be removed for RAM replacement.
I do not possess a touch device, sorry.