I just bought my blackview P2 and I flashed android nougat 7.0 one and half weeks later.

I notice heating/over heating WHEN CAHRGING the the phone - is this normal ?

the phone heats up because of the quick charging, energy equals heat the more current you put through something the hotter it gets

The way the phone is overheating during charging , the temperature is so high I don't think its going to last 6 months before the battery gets burned out/destroyed from the high heat.

I want to disable fast charging but I can't find where to do so in the settings.
Can you help please ?

Blackview P2 also heats up when I am using it normally and without connecting to the internet.
My other two phones - jiayu s3 (on custom ROM resurrection remix 7.1.2) and Samsung galaxy grand neo plus (on stock ROM) don't heat up when I am using them in a similar fashion.

When I use WiFi or data , blackview p2 heats up much more than the other two.

I do notice the phone getting hot when in high use, however I don't think it is more noticeable than other phones I have had