I currently have a page viewer on my SharePoint site. One of the links is outdated and needs to changed, is there a way to update/change the link without doing HTML?
What do you mean about "One of the links is outdated"? Where is the link? Is it a link display in the page viewer web part? Or it is the link of the page viewer web part?
If it is the contents displaying in the web part, you can go to the source location to directly change the link.
(Page Viewer is the web part that displays another Web page on this Web page. The other Web page is presented in an IFrame.)