The biggest part of being a DJ is being able to pick songs that you know people like and to stay up to date with the latest music in the genres that you spin this involves some work.. visiting different sites that have the genres of music you like and doing a little searching for the genres you like.
Since you mentioned in indie search google for indie Radio stations these can be good source for finding new music just look at there recently played list .
Beatport another https://www.beatport.com/genre/indie-dance/37/top-100 has top 100 latest indie dance tunes for example.
Spotify if used correctly another great place to discover new music by searching for specific genres then going through the user created playlists searching indie hits or indie 2020 etc.