This is either a chance to develop your “mobile” DJ skills (meaning you can play whatever to whomever whenever) or to decide that you want to be a genre/club DJ. The main difference that in the latter case you will only (want to) play in rooms with an audience that digs your genre(s) of music. It’s a rather significant choice. If you want to go mobile you will need to get an appropriate collection. And while generally that is not that feasible in two weeks, it IS possible to throw together the 80-100 tracks to play in a two hours slot and get familiar with them (making 3-4 track mini-playlists will be a savior here). Clearly it means investing in some music and the time to select the music, put together the (mini)playlists, prep the tracks and listen to them for the next two weeks to get familiar with them.
If you feel mobile DJ-ing is not your cup of tea then you probably should politely decline. No fun DJ-ing too far outside your comfort zone. And that goes as much for you as it does for your audience.
Also you need to be clear with the organizers on what style/mood they expect you to bring in the afternoon. This can be as broad as chill, lounge, easy listening, upbeat background to top 40 dance(able) stuff.
Hope that helps some. Good luck with your choice!
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