"Charity" doesn't have a verb form. The typical verb used with it is "donate to charity."

People often say "give to charity". Although the multiple meanings of "give" cause the verb to be less precise than "donate", by adding "to charity", the expressions means the same.

Question correction: I have a homework assignment: I need to find forms of different words. I have a problem with the word "charity" -- it's a noun. And "charitable" is an adjective. But do you know the verb form?