Application that doesnt minimize a certain app. ?

So , my brother is a coder and he got alot of work and his so bored on coding stuff.
He wanted to watch movies while coding ,
so he favored me to search a application to not minimize a certain application ,
like internet browsers and such .

If your suggesting to resize the application but the
screen is so small .

thanks in advcance for those answers .

Can you provide more detail? I'm confused. I'm not understanding exactly what you're saying.