If my ffiance and I get married in ghana will it be legal in the u.s and once we get married will he be able to leave with me when I leave or will he have a waiting period before he can leave I have heard several different stories on this from different agencies.

A marriage is legal in America as long as it is a legal marriage. A gay marriage for example would not be honored in many US states. If you are marrying a 2nd wife, it would not be legal in US. But if you are just getting married it is legal.

Your new wife will still need a visa to enter the county. Often this is done with a touist visa and a change of status will be applied for after getting to the US.

If you get married in Ghana, you will have to petition spouse visa for your fiancé in order to enter US. The chance to obtain visitor's visa in Ghana is equivalent to zero. The process takes about 10-12 months.