If you have an Xbox One (maybe 360 too, I don't know) and you want 1000 Gamerscore very easily, if you downloaded 'Forza Horizon 2 presents Fast and Furious' (it was free, not sure if it is now) then playing that for a little bit will ramp you up some Achievements very quickly.
There's only a handful of things to do, most of which you'll accomplish in 30 mins of play, and it requires basically no skill or challenge. Literally just play the game.