I need some assistance to size an image on a page.
I have added the image and set it to “full”, but when it displays on the page it has a max width of 730px. I want it full width. I “inspect” it and see the following greyed out, so it cannot be changed
You should set large image for that page on your site so that it will occupy whole width.
If you are setting large image for the page but the image is displaying small on that page then it seems this is happening because of the Jetpack plugin Photon module that you are using on your site so could you please try temporary deactivating it or its Photon module on your site?
This jetpack photon module is not updating the images stored on wp.com so to resolve the issue either disable this module or update the images on wp.com by contacting jetpack support team.