The National Endowment for the Humanities (Resource 1) offers several grants and fellowships to fund research programs, including grants for translating literary and historical material. Many states offer grants to state residents, while others offer grants based on a proven record of excellence in biography writing.
Before you apply for a grant you will need to take the time to find out if you meet its eligibility requirements. Some grants list eligibility by a candidate's age, location, subject and type of writing, etc.
Each type of grant has specific criteria about how to use your grant money, including not using it to fund political or social projects, or the available time period to use it before it becomes unavailable.
Depending on the criteria, some organizations provide an application, while others provide a Request for Proposal (RFP) which lists guidelines for how to apply for a specific grant, including word and page count, and information. (Reference 2)
A professional proposal writer will help you find available grants for biographers and also write your grant proposal.