I had missed this forum, but now that I have found it, you experts may get tired of questions from a dumb really old man with only windows experience. I am a simple kind of guy, so don't care for the most elaborate stuff. I got so fed up with a 7 month old MS Surface laptop that I went out and bought a el cheapo MacBook Air M1 on a Walmart sale. Have found that I absolutely love the speed with which this thing can traverse through the internet, it just runs circles around any windows machine I ever owned. You almost never see it loading a page, they just appear instantly when asked for. So perfectly happy about that. But I cannot figure out a way to deal with my photos on it. On windows, I just make new folders for each month with sub folders for special events within that particular month and download my photos (all jpegs - no RAW) off sd cards to the appropriate folders. Then if I want to view or perform any edits to my photos mostly use FastStone which is quite simple and has plenty of flexibility to keep me happy. I also have used IrfanView, windows photos, and Nikon View NX studio.
On the Mac, I have made some folders, but not figured out how to open these photos in a program like FastStone (which I have yet to find), edit them and save back into the folders. My editing operations are very simple involving only cropping, occasionally tweaking exposure or bringing out shadow detail, sharpening for web viewing or prints and resizing as required for web sharing.
Any really simple suggestions? I'm not a fan of long drawn out technical details, so will ignore those types of suggestions

and listen carefully to basic types of assistance.
Thanks for listening and any simple helps appreciated.
Edit to add. I do still have windows 10 and 11computers and for now continue to use them for my photos, and if that seems to be the better solution for me, I will listen to that suggestion also. Just sorta wish I had a better way to integrate into the Mac.
Just chiming in with my 2¢ worth.
I've never been a Windows user, but have used most of the option available on the Mac over the last 24 years of using digital photos.
I found that in the modern era, trying to use a traditional folder setup, and saving copies to JPG was just too messy and complicated, and all too often open to user errors.
Then long came the non-destructive workflow system (often called DAMs - Digital Asset Managers) - initially this was Apple Aperture, and Adobe Lightroom. Others soon followed.
However, for the basic user, on a Mac, Apple Photos is a great start. It's far more capable than first realised. It's fully non-destructive (so the original files are never edited, it always works on a copy internally, so you can always revert back to the original). The editing tools are quite good too for a start. It's also already installed, integrates fully with the Apple ecosystem, and has no extra costs involved (other than iCloud storage if needed).
It's also quite expendable too, many higher level apps offer the ability to add extensions to Photos, so you can use Photos to manage the library, and the external apps to edit them. However, I'd start off just seeing what Photos can do first, you may be surprised.
Others have mentioned that it syncs across iCloud, but you don't have to use it that way. You can turn off iCloud, and just store everything locally. You can also choose to not store the images in the Photos library, but keep them in an external folder system if you wish (called Referenced mode). However, it's not recommended, as it's not known for being all that reliable, and doesn't offer a reversible option once you import into the Library for the 'managed' option.
You mention needing to keep photos separate. That's also possible. Photos can work with multiple Libraries, you can either hold 'Option/Alt' at launch, and choose a library, or double click a library. there's also a good app by Fat Cat software that offers more advanced library management. Be aware that one one library can be used to sync across iCloud though (if you need that.
All said, you can also easily filter images in your library, should you find it's better to put them all into one. There are smart albums, and keywords, which can make it possible to separate out collection of images.
I personally keep the whole lot in one library, and have a 2TB iCloud account (60,000 images is using 1TB at the moment, and it took that 24 years to fill).
I found it so much more convenient to bung the lot into a full iCloud library. I don't have to go hunting down images in different locations, and they're all available on all devices. that's hand for me, as I use an old MacBook Pro to import and manage the library, but I use an iPad Pro for editing.
I also use Nitro (and previously Raw Power) for most of my Raw photo editing. It's produced by Gentlemen Coders (Nik Batt who was a top developer for Apple's Aperture and imaging division). It works seamlessly with the Photos library, and offers much more in terms of editing and management capability.
Others have mentioned the Take Control books, and I'd certainly recommend getting some of those if you're new to Macs. Even an experienced user finds those useful ;-). they often have sales on, and there is a discount for multi-buy (Its worth taking advantage of that).
Good luck, and all the best.