Outdated google codelabs, set up a pwa

Has anyone successfully gone through the google codelabs?
specifically how to setup aspects of the pwa?

Ive been trying to get through the google tutorials on progressive web apps, but none of them seem to be up to date or working as they describe. for example this codelab doesnt work:
push notifications

and it seems to be a duplicate of the same content as the below link:
push notifications #2

So which one is current? Is google just putting out random content without updating it just for the sake of putting out content?

So far in my experience of going through their codelabs they have multiple versions of the same things found on different places on the internet, none of them work, and by work I mean that they are not producing the outcomes as explained in the tutorials. So if none of them are working as described in the tutorials.

not posting this just to complain, I would really like to know how to set up a working pwa with all the features, push notifications, save to homescreen, payments etc… but going through their tutorials I dont seem to be getting anywhere. Ive posted issues on their repositories and their reply was:

we don’t author or manage those codelabs, and it seems anyone can author codelabs that get published to that site (according to https://github.com/googlecodelabs/tools). This one looks like it was written by Google Developer Training, you’ll probably have to venture over there if you’d like to update the codelab :slight_smile:

I dont know how to update their codelabs, but would like to see some tutorials that work and can teach you how to setup/convert an existing app to a pwa… I know theres a myriad resources for this online, so do you guys know any that are up to date and that actually work?