I am a Nepalese, can I go to Macau with a visit visa from HK

"In the light of these needs and the recent social situation in Macao, considering the conditions of different countries as well as the purpose and status of their nationals' past visits to Macao, the Macao SAR implemented the following measures starting from 1 July 2010: nationals of Bangladesh, Nepal, Nigeria, Pakistan, Sri Lanka and Vietnam are required to obtain an entry visa before visiting."

So yes you need a separate Macau visa which can be obtained at the CVASC in HK.

Hi, How long does it take to get the visa? What is the service fee?
I am now in HK but will go back to Nepal next week.

Dear, the process time is usually 4 working days. It costs HKD550 for a single entry type.