Sidebar links not working

Hello,

I am working on building a site with child themes. I created a custom sidebar to use as a nav. But when I’m on a page that is not the front page, the links do not work. When I am on the front page they work fine. It seems that when I click on a link from any other page, it appends the url onto the current url, which of course isn’t a page so I get redirected to a 404 page. How can I fix this?