Many years ago I purchased this very pristine G4 iMac from a very small local electronics shop. It is very well kept and I figured that a retro computing collector like me should have one. Or whatever other excuse I had to find to self justify the purchase.

Fast-forwarding today I have a project where all I need is a baby kiosk for prototyping some ideas for my wife's business. As I turned this little pretty dinosaur, I learned a few things, and in that order
- It still running!
- The internal battery that holds the clock is definitely less alive than once was.
- Any website I tried to browse with a secure connection gives me an error that my clock isn't set right.
- The OS is so old that I can't run much of what I would need for the project

Certificate issue
The certificate of all certificates present on that machine is expired and of course, any site that checks against that root server tells the browser that the situation isn't safe. After putting my lab coat on, I did the following:
Opened the terminal and typed
wget https://x1.i.lencr.org/
I couldn't download that certificate from the browser well for the same reasons they sell those special scissors to easily open sealed plastic packages in the same packaging that they are supposed to easily sell.
wget by default doesn't check for the HTTPS protocol so it downloaded the certificate without hesitation. Good boy!
I then imported it into the keychain and stored it at the system level rather than the current userspace.
I then searched for the imported certificate: ISRG Root X1
double click on it, open the Trust menu, and change "Use System Defaults" to "Always Trust", then close that and enter your password to confirm the change (if prompted).
Job one is now addressed.
Installing Linux on PowerPC Machine
Installing Linux nowadays is a simple as any other FAANG supported OS. However, when it comes to giving Linux life to a PowerPC the ride can be a bit more of a hit a miss.
General consensus online is that Ubuntu Mate was the best option but then as anything that humans try to agree there was general consensus that the option was as bad as putting mayonnaise on peanut buttered bread.
Since I wasn't sure what to do I started with what I knew I had to do, find an image that I could give a go and burn it on a DVD.
I downloaded the 32 bit for PPC of Ubuntu 16.04 "Xenial Xerus. Again wget here helped to get the job down because even Chrome on a modern machine didn't want to act on the link. The mystery thickens!

This list led me there and perhaps it will help somebody else in a slightly different scenario than mine.
I downloaded SimplyBurns from sourceforget.net which runs on PPC. Once the DVD was in the bay, I held down the C key which as memory served was supposed to force the reading of the CD-ROM unit. It worked!
The DVD ROM on the machine is either as dusty as the ears of my grand-gram mother or has some hardware issues - after the first boot didn't want to boot anymore. It kept opening and closing very quickly the bay.
All done and done
It took forever to install and this was over Ethernet but I am fairly impressed by the quality of the build and overall speed. Perhaps because my expectations were below low or because what I intend to do with the machine is very basic and it shouldn't require many resources to do the job. (nodejs)
I hope what I did helps someone out there and in particular the gods of all drivers. Mine wasn't particularly kind on the graphic card...
peace out Linux on mac in.
Resource
This guide was helpful to figure out some essential steps