I am trying to:
Put next/previous pagination in a blog view. This is the code that I am using. It is standard code from a template View that I import regularly:
When you insert the prev/next pagination controls there is an option to show them on the first and last pages even when not needed (it adds an attribute force="true" to the shortcodes).
So on the first page, the prev link will be disabled, it will just show the text, but it won't be a link.
That is happening in your View for both the prev and next links, because...
You have added a limit=3 setting to the View, and the pagination settings are set to display 7 posts per page.
Because there can only be 3 results in total (due to your limit setting) there is never another page to paginate to, hence text is displayed instead of links.