Before one can enter into the USA as a student, you need to have some authentic documents. These documents include an Admission Letter, Scholarship Letter(if any), F1 student invitation, Confirmation of Payment of Student and Exchange Visitor Program (SEVIS), Bank Statement of sponsor. I believe these are the essential documents your may need. Including passport and certificates. For your certificate, (not sure of the university you completed) check in at the national Accreditation Board in Accra and check for it Authenticity – not all universities in Ghana are accredited.
Bank statements should be from Someone Overseas or here in Ghana who have a required amount of money to prove that he/She can take care of you during your period of stay. Aside these, admission letter, F1 student invitation and scholarship letters come from the school you applied so if they rather coming from agents/individuals aside the school then you must consider looking into that. SEVIS form also comes from the Home Land Security so if it’s also coming from individuals then there is a problem. If you have all these documents, all you need to do it to prove yourself at the consulate on the day of your interview.