Broken links, redirects and so on

Hey,
I’m still having problems with the gallery. I’ve noticed that Ahrefs is throwing up more and more issues containing:

links to 404 pages, 4XX pages, links to broken pages…

example: https://www.mydomain.com/?attachment_id=6713

Is there any way to fix this? I love this gallery, but I would love to solve all these issues. Thanks in advance for your help.