How do I set up an admin route for a web administrator? [closed]

I have tried creating a route say '/admin' where an admin can login from but I believe that is a bad practice. Is there an existing way of handling such routes. If i inspect some popular websites i.e stack overflow.com and type https://stackoverflow.com/admin i cannot get an admin route and neither can it be listed in a web crawler tool.How do handle such admin routes ?