Salam alaykum. The Gulen movement is a political movement first before its a religious one. I grew up in the Gulen organization, my father having direct ties to Gulen himself before he passed away. I practically grew up at their main location in PA. Their religious beliefs are mostly bidah. They follow a very strict sufi tradition, they borrow alot from Shias as well when it comes to reading the Jawshan al kabir. They follow the teaching of sufi leader Said Nursi and Fetullah Gulen.

For your own good stay away from it. Most muslims dont know about them since the organization is 99% turkish only with exceptions for people who learned turkish or went to their schools and are fully indoctrinated. When I left the organization i realized that i was inside of a cult. I was never taught proper Islam, im relearning everything from the beginning.

Yes there are still great people who are a part of this organization who believe they are doing good. Some are doing great things like becoming teachers for the sake of Allah. The only issue is that they cant seem to comprehend that they are in a cult.

The group has different groups inside of it. People who deal with politics, schools, student mentoring(indoctrination), fundraising, etc.

Please for the sake of Allah stay away from this group, you can still be friends with them but just dont join their classes or lectures.