Create a field to add HTML link to URL in a contact field with image names

I want to create an HTML field that links to a website folder with images.
The website folder has images.
Each contact page will have a different image name in the field.
The goal is to use an email template that references the HTML field and generates an email with the contact image inserted into the email.
Creating an HTML field is a simple process using the CRM interface.
Getting the field to link to a specific URL e.g. .xyz Domain Names | Join Generation XYZ is the challenge.
After creating an HTML field what steps are needed to include a link to the website folder with images, please?