painting exterior wooden windows

[mbon]

I need to repaint wooden exterior windows to home around 10 years old and window paint is peeling.

I bought ronseal 5 year woodstain but after testing on wooden exterior door noticed that those parts sanded down to the wood do not stain as dark as the areas that had previous paint on them.

Am now thinking that wood stain is not what I need for the windows and that it might be gloss paint.

Can someone help me with difference between woodstain and why it says on tin it is for exterior windows (its ronseal - does exactly what it says on tin!).

This is my first time painting exterior windows but not sure what I need to do and what paint I need so would any advice would be much appreciated.