Often times many try to learn something because they think they should, and not because they want too or need too.
There are a lot of courses out there that teach out how to learn, one specific one being the learning how to learn from Coursera.
But to be honest, I believe your underlying issue is anxiety/depression, and not "how to learn"
I think your time might be better invested in seeking a therapist (betterhelp.com), the ROI from a therapist should unblock you from the difficulties you are having.