I had to change my theme because the old one wasn’t supported anymore. I have pages with 60ish images (not gallery). I’m trying to add a new one in the middle (insert block before/after). Selecting image from my computer and then it looks like it’s trying to add it but the little circle just keeps going around and it never adds. Help?
That sounds more like an issue related to your connection, rather than an issue with WordPress.
How large is the image you’re attempting to upload? If possible, resize the image to the smallest size you’ll need for your site before uploading it.
If you upload a full-resolution image, it may cause problems for a number of reasons, not the least of which is that your server may have to ‘crunch’ the image unnecessarily. That could account for why the icon is spinning.
Resize the image and then try again?