Samsung Tab 3 Won't Boot Up

[Noggin The Gog]

It's a GT-P5210 I think (the print is very small, faint and on an un even surface)
It tries to boot but sticks where the SAMSUNG logo has a bluish fading shadow.
I've tried all sorts but to no avail.
I've downloaded Odin and Kingo but think I need other files for them to load
Please can anyone help?
(warning I'm old, slow and sometimes grumpy but always ready to learn
Many thanks