When I start my OS it takes long

Kernels are software so they can crash or hang too, doesn't happen to often but it can. You can add the line with # back to /etc/crypttab but that won't make a difference to what just happened. Anyways have fun with learning GNU/Linux and with PopOS!
If it continues I guess I make a post
The changes we made can't be the cause of kernel crashes or kernel hanging since we removed the activation of a swap device which wasn't setup in the first place. You can first try reinstalling the kernel.
sudo apt reinstall linux-image-$(uname -r) linux-image-generic
If that doesn't fix your problem create a new topic.