In classic SharePoint sites, it was possible to redirect users to a different site using a few different approaches. But modern SharePoint sites are more restrictive (for good) and offer different features that require different approaches.
Fortunately, if you need to redirect users when they try to access the homepage of a specific site, this can be easily achieved using a simple no-code solution.
News link for site redirect
The solution for modern SharePoint site redirect basically consists in creating a News link to the target site and set the News link as the homepage of the site. When users try to access the site (homepage), they get immediately redirected.
On a modern site, you can easily create a News link from the New menu on the site
Or from the Add menu on the News web part
Provide the URL to the target site that you want to redirect users to, and a Title for the page.
Next, simply access the Site Pages library, right-click on the newly created item, and make it the site homepage. It’s that simple!
But what if the site is a classic site? Well, you can still use the same approach as it’s so simple.
But how do you create a News link on a classic site?
Simply create a new modern page on the site, add the News web part to it and click on the Add menu