It depends on how you're using it.
If by 'staff' you mean a group of people (office staff), it is already plural and doesn't need an s after it. Possessive form would be staff's.
If by 'staff' you mean a stick (I'm going to whack you over the head with my staff), then the plural would be staffs. In this case, the singular possessive would be staff's and the plural possessive would be staffs'.
do you capitalize the word protestant
No, you do not capitalize the word drama.
Capitalize the word architect only when it is part of a title.Example:Senior Architect, Joe Smith
You do not capitalize the word quarterback unless it is at the beginning of a sentence.
No, but you capitalize the name of a biome.
No, "engineering staff" should not be capitalized unless it is the first word in a sentence or part of a title.
do you capitalize the word protestant
It is not necessary to capitalize the word "yo".
No, you do not capitalize the word drama.
Yes, you must capitalize the first word, UNLESS it is a small word, such as "It" or "A" or "The".
Unless "it's" is the first word, there is no need to capitalize.
No, you do not capitalize the second word in the complimentary closing.
Yes, you should capitalize the word after a comma in a sentence.
In a title, you generally do not capitalize the word "for" unless it is the first word or part of a proper noun.
Capitalize the word "to" in a title if it is the first or last word, a proper noun, or a verb.
Yes, you typically do not capitalize the word "to" in titles unless it is the first or last word.
No, unless referring to a specific title or name. Generally, "administration staff" is written in lowercase.