is there need a transit visa of Hong Kong on Ghanaian (Africa) passport

yes, All Ghanian nationals (except holders of Diplomatic and Official passports) are required to hold a valid visa for the HKSAR for whatever purpose (including those who are in transit and remain on the airside). Holders of Ghanian Diplomatic and Official passport may visit the HKSAR visa-free for a stay not exceeding 14 days.

thank you very much for the reply. can you send me transit visa forms.

You can download the Hong Kong visit/transit visa application form from https://www.travelchinaguide.com/embassy/pdf/hk-new.pdf