How to create permanent links for photos?


I’m new to nextcloud, sorry for my basic question.

I’m doing a spectral library and to support the spectral information I thought to add some photos. Since the file can only contain txt. information I have to get permanent links from the photos (the photos are already uploaded in nextcloud). I noticed that I have a link associated with each photo, but are those links permanent (they will not change in the next 10 years?)?

I have been trying to find such information but is not clear if the links are permanent or not.

Any help will be much appreciated.