Half Black MacBook Pro Screen

That is very similar to a tire that is only flat on the bottom. It's still flat, and like needs to be replaced.

as a work-around, you could connect an external display or TVset with adapters.

what model-year and screen size?

 menu > about this Mac

if that machine is still meeting your needs, it can still run up to Monterey, but will not be getting security updates after about a year from now when that years' MacOS is issued.

The entry level MacBook Air starts at US$999.