For lots of free resources and to join a community of other students studying for the MCAT check out r/MCATBros on reddit or join an MCAT Bros Facebook group! The MCAT Bros facilitates multiple different student groups such as the "MCAT Study Hall" where you can ask and answer any content-related questions for the MCAT.
Another resource that the MCAT Bros offer are Psychology/Sociology and Biology review packs. A link to the dropbox can be found below, or you may access the dropbox through their reddit page.
Khan Academy Transcription Project for MCAT by MCATBROS {KA Notes} - Google Drive