open lightbox from button

I am a little inexperienced in HTML and I need help creating a button that opens an "image" in a lightbox and an "ajax" in a lightbox.
Could you tell me what the lines of code would be for each case please?
I have attached a reference image called "button to open a lightbox image.jpg" with the button created, but by adding data-lightbox="image" to the tag or data-lightbox="ajax" and the tag the button is misconfigured.
I look forward to your help.
Best regards,

Hernan

I also have problems with Instagram blocks. They are outdated. The code is from 5 years ago so it doesn't work. Can you update information for Instagram please?