Hey man, I experienced something similar to you. I was in evangelicalism for a long time, and didn't really understand the Bible.
SermonAudio is your friend. If you have a smartphone, use the app and download a bunch of sermons and just listen to them.
I honestly think that something that would help you is to go through the Heidelberg Catechism. It is a staple of many reformed churches and is preached on regularly. I would get a copy (or just go online)
http://www.heidelberg-catechism.com/en/
Then go on sermon audio and listen to a series through the catechism.
Here is a complete sermon series (52 sermons) from Joel Beeke's church:
https://www.sermonaudio.com/search....ies&subsetitem=Heidelberg+Catechism+Season+09
And one from a really good URC preacher, Paul Ipema:
https://www.sermonaudio.com/search....eries&keyworddesc=Heidelberg+Catechism+Series
I wish you nothing but the best.