I don't want to create a file shortcut on the desktop, I want to create a shortcut inside the Pictures folder to the DCIM folder. My mom is able to handle tech stuff, she used to work for HP. But she's getting forgetful and keeps forgetting that I have told her multiple times that her photos are under DCIM and not Pictures. If I have to root her phone to make this work, that's not an issue, I have plenty of experience with that, and have already researched how to root her particular model of phone. I believe the version of Android on the phone (AT&T LG V20) is 7.0 Nougat. Thanks for any help you can offer!
What you are looking for is called symbolic linking
ln -s command is your friend. Now depending on your device and the file manager you use, this process can differ. I don't think you'll need root for this, but if your device doesn't come with symbolic linking by default, you'll need root to add this.
And like the other comment said, it's better to use a Gallery app for photos rather than doing this.