ahead vs beforehand

ahead and beforehand both are adjectives.

Word	Noun	Adjective	Verb	Adverb
ahead	No	Yes	No	Yes
beforehand	No	Yes	No	Yes

As adverbs, ahead and beforehand are synonyms defined as:

Other synonyms of ahead include in advance.

ahead (adjective)	beforehand (adjective)
having the leading position or higher score in a contest	being ahead of time or need

ahead (adverb)	beforehand (adverb)
at or in the front	ahead of time; in anticipation
ahead of time; in anticipation
in a forward direction
leading or ahead in a competition
to a different or a more advanced time (meaning advanced either toward the present or toward the future)
to a more advanced or advantageous position
toward the future; forward in time