jmoore, I use this site to reduce my file size. It doesn't do much more than that but that makes it easy! As an added bonus it doesn't set off my virus scanners:
https://www.reduceimages.com/
I just use the default settings it offers and then download the file from there, then when I upload it here it is already in the Downloads directory which is a default search option here. Periodically I do some file management of my downloads directory and store the images in my quilts folder.
I know Macs are different in some details but as an added help, I reduce my overall main window size to about half screen on the bottom half and so the drag down spot for the graphic is visible (this makes sense if you visit the site). It stays at the shape I defaulted it to because I dragged in the corners. Then I click on File Explorer option and I've resized that window to fit above the reduced main window, so I just drag my image from one screen to the other.
Because of my vision issues, I do use rather large pictures for the default in my file manager and not file names. It really is just drag and drop.
Photoshop is awesome and does many things but I don't have it on this system. My issues are using older technology, so I'm transferring from an actual digital camera and the camera software is not up with today's standards and options! I mean, I think we were still using disks back then...