If I understand your question correctly, you want to add a URL on your app home page or any page and when users click that URL, users need to redirect to that URL defined site.
If this is the case, I have a simplified solution to you. In Studio Pro, add an attribute by name URL in entity. Then on a page where you want to make it visible, add a list view with newly created entity. Add a button but change it to link. Then add a caption to it. On events, give open link, link type web, use attribute type and select the URL attribute. Then provide edit button(should be visible to admin only) beside that button. On hitting that edit button, show a page with the entity you created newly. And text box field mapping to URL attribute. Then save and cancel buttons.
Now, on UI as an admin you can see only the caption, which doesn’t lead to anything. Now edit the field and add the URL which you want to show on clicking that caption. Save it. Now on clicking the caption, you will land on the site which you want to show.
Instead of editing, you can add it at the backend as well. By giving edit button on UI, dynamically you can change, whenever required.
Hope this made your work easier!
If you want the URLs to be linkable, you’ll need to use the Deeplink module to provide a route to them. You’ll also want to be able to set the URL so it shows in the address bar. To do this use the Set URL widget on the page.
Hope this helps.