I'm looking for a way to redirect user when they want to access for example www.domainname.com/products/car/volvo/car1 to www.domainname.com/products/ i'm using umbraco to build the site
Rather than handling such requests from the application's web.config, you could have the web server (IIS) redirect the requests. Please refer below link on how you may do so.
https://www.iis.net/configreference/system.webserver/httpredirect?showTreeNavigation=true