Do Ghanaian citizens need a medical and police report before obtaining a visa to visit England? Should the first two items cost £350?

Nope, all part of a well documented SCAM

You're being scammed. Don't send any money... or "moneys" as they usually call it.

No they do not need them.

Even if they did, they would only cost a small portion of that.

This is the most famous scam in the world