I got a great source to learn punjabi online. punjabi.softvirtualtraining.com/courses/ they not only provide instructor based punjabi learning but also help the students to recite the bani.
I don't really know if there is any one answer except to read a bit and practice a bit every day. It's also good to have a community where you can ask questions if you get stuck.
This gora dude in the video you posted doesn't exactly have the best accent. He is incorrect to an extent as well, ਛ (chh) does indeed sound more like "sh" than "ch" in punjAbi, whereas he makes them sound the same, which can make a big difference and can be problematic, like the difference between ਛੋਲੇ (chhole, as in the food) and ਚੋਲੇ (chole, as in clothes). Also, he is incorrect about ਖ਼, ਗ਼, ਜ਼, ਫ਼, and ਕ਼ being used in pAkistAn. We don't use gurmukhI in pAkistAn, we use shAhmukhI. Also, qaaf (ق is definitely not the hardest arabic letter to pronounce for me (although I'm not sure about for other people); the hardest for me are ayin (ع and ḏaal (ذ.
I'm not sure if you still visit but if you do, you and other visitors might find this YouTube clip very useful. It's the best explanation of the Gurmukhi alphabet I've found so far:
I'm not sure if you still visit but if you do, you and other visitors might find this YouTube clip very useful. It's the best explanation of the Gurmukhi alphabet I've found so far: