sounds like you are looking at the wrong teams trying to find team members. I've had success raiding with LFG teams and never having completed that raid before. Basically all of the raids i completed in D1 and D2 have been done this way. If you arent looking for a carry, learn as much as you can, even watching different "how to videos" multiple times. Hopefully you already have the guns they suggest to own in the videos, but not always necessary. Find a group where a sherpa is trying to help a friend. Ask to join and let them know you are also looking to do your first run. When the Sherpa is explaining the raid, pay attention, dont be distracted by Netflix, Youtube or your cellphone. I like to repeat what the sherpa said so they know i am serious and have a clue of what is needed. Ask questions if you have them. A clan with helpful members that raid can be an easy way to find people to play with. Typically they ask you to help others in the clan after they help you.