What's the process to have someone from ghana come to usa to visit?

They get a passport form their government and a VISA from the US emabassy. The cost is 100 dollars or less. There is no required money to be in the bank and there is no bribes that have to be paid.

Ghana has the worst rep for fraud, there are 1000's of people each day cheated by people using dating sites or email to pretend and come here. Thre are rooms full of people using the same passport or ID often to milk people in the US, Canada and Europe out of money

First obtain Ghana passport... it costs about $100.

Then apply for visitor's visa at US embassy... visa fee is $131. The fact is rate of visa approval is near zero because the individual must be able to prove that he/she has sufficient funds for the trip and must have strong ties to their home country.

There is warning on US embassy page, please read before you become the next victim of dating scams. https://www.askmehelpdesk.com/visas-passports/ghana-passport-visa-fraud-288039.html

If you are confident that the one you're talking to is genuine, it's better to go there and see for yourslef.