Best way to be done with task in wordpress

Hello!
I’m new to development in WordPress and I have one task to do. I create my own theme.
I have images that will be links and when site visitor click on image I want to load data in same page template. This data is some parameters of this clicked image. I think is good idea to create custom table in DB and used for this. Also I want website administrators manage this data from administration section.

For me is very helpful if someone know best practice and best way to do that.
Thank you!