Who is a songwriter and what do they do? The songwriter writes lyrics which are set to music by composers. S/he or she may write lyrics for specific singers, or for no singer in particular.
What are the activities of the job? If s/he knows the singer for whom s/he writes lyrics, s/he will know the style that should be followed; if not s/he or she writes according to his/her inspiration; if a singer asks for some changes in lyrics, s/he will make them.
Where is it done and under what conditions? The songwriter usually works alone and can work at home, too.
What tools/equipment do they use? Paper, pen and his/her inspiration.
What do you need to succeed? You should have talent and imagination. Having studied music or played a musical instrument is also valuable.