Looking for advice on where to start learning how to fix a windows profile that has corruption or bluescreens, with CMD or PowerShell commands

Let me Preface with this.

My question in TLDR format is: What's a solid way to learn PowerShell and CMD commands in a way that is tangibly accessible for someone who really only uses dism/online [or the image:(drive name): variant] /cleanup-image /restore-health, sfc /scannow, and Windows Media Creation Tool to repair Windows?

I keep seeing Microsoft and other sources saying to fresh load Windows as a default fix.

I've even heard the nightmare stories of a customer bringing a computer with a failing HDD to a repair shop, just for the repair place to give the customer a fresh Solid State Drive and send the customer on their merry way with a fresh load of Windows and their documents and pictures moved over and that's it.

I know how to manually move app data and remap folder structures to rebuild someone's Windows' Profile (once it's too far gone on a dying or failing HDD/SSD).

Most people I know are completely content with their shortcuts and bookmarks being there along with rebuilt or redownloaded steam games when they log in after staring at a blue screen for days.

As for me, I want to be able to genuinely fix it/further understand how Windows works.

For Example:

Let's say: the repair option with a Windows Installation Media or reloading Windows to fix someone's corrupted profile doesn't suddenly bring back their login page after hours of crossing fingers and consulting rocks.

My assumption would be to go down the rabbit hole of learning a coding language specific to languages that Windows utilizes.

For context: I've worked in a Locally-Owned-Computer/Phone-Repair-shop for close to 3 years now.

I usually do hardware repairs like mother-board swaps, phone screens, custom desktop builds and I'm fairly confident with Windows 10/11 as in my personal life I am a certified autistic nerd and proud gamer XD

I want to delve into maybe coding or PowerShell as a way to start learning how to fix Windows issues on a deeper level once you get the dreaded "srt.trail" message of doom...

My plan is to sign up for Microsoft's PowerShell Courses and maybe look into Dism a little more? (for when rebuilding the boot loader doesn't fix it)

If anyone has any suggestions: I'm all ears, and thanks for any info!

I figure real people's opinions would get a better answer than Google saying, "Learn Python or Linux, scrub."

Thanks!