easy (command line) way to transfer a folder of photos from Android phone to Linux Debian desktop I have a RedMi note 7 phone model M1901F7G, running Android 9PKQ1.180904.001; I don't want to root my new phone (it is a gift from my wife, and I don't want risking bricking it).
I am an expert Linux user (since 1993) and developer (e.g. of bismon), preferring command line things.
The album on the phone contains a captchas subdirectory.
The phone is USB plugged to my Debian/Sid AMD2970WX desktop (I have sudo access to it). Kernel 5.3. X399 chipset. MSI X399 GAMING PRO CARBON  motherboard.
What is the detailed and quickest procedure to transfer the more than hundred JPEG files from the captchas/ subdirectory on the phone to the $HOME/Pictures/ subdirectory on the Debian desktop? I will do that occasionally (once a week perhaps), from home, using USB3 cable. But I want to avoid 500 clicks on phone or desktop.
I am able to transfer each individual photos (in about 5 clicks). I want to transfer a hundred of them.
I don't exactly understand the &quot;USB debug mode&quot;. Please name free (as in beer) Android applications related that, or finger actions to enable it. I believe it is in the settings menu.
Of course I do like starting gmtp on Debian. I don't want an alternative to MTP. I just need to learn how to use it (and likewise for adb).
Bear in mind that I am not familiar with Android in practice, and that my sight is not very good (since I am 60 years old - had cataract surgery), and that I am not a native English speaker. But Unix commands, I could teach them even with moderate fever (since my first Unix was SunOS3.2 on Sun3/160 workstation at work around 1987, and I was given root and physical access to it). First Linux was Slackware, 0.99.12 kernel, around 1993 (on dozens of floppy disks, i486 motherboard). Getting X11 running at that time required kernel recompilation for the graphics card.
Take into account that (perhaps by mistake) I configured my phone in French. I cannot identify an Settings -&gt; USB debug or Settings -&gt; Developper Debug thing. Maybe I should by some app, but which one?
To pull a folder from the sd card, you can use adb tools using following commands in terminal:

cd $HOME/Pictures/
adb pull /sdcard/captchas/


It will pull all the files from /sdcard/captchas/ to your Pictures directory.