How do I change the URL for Razor pages from the default format like
http://localhost:5088/Home/Faq, to a specific URL such as
http://localhost:5088/freq_asked
Based on your shared code snippet and description, in order to change the URL for Razor pages in an ASP.NET Core MVC project from the default format we should use Conventional routing
As you may know in asp.net core regardless of its version it has ControllerEndpointRouteBuilderExtensions that includes the method MapControllerRoute we can use that what you are trying to achieve.

First of all, you should use MapControllerRoute to define custom routes in your Program.cs file. Must remember that custom routes should be defined before the default route to take precedence.
In addition to that, make sure that your controller and action method names are consistent with the routes you are defining.
Let's have a look in practice how we can implement that:
Program.cs file:
app.MapControllerRoute(
name: "customFaq",
pattern: "freq_asked",
defaults: new { controller = "Home", action = "Faq" }
);
app.MapControllerRoute(
name: "default",
pattern: "{controller=Home}/{action=Index}/{id?}");
app.Run();
Controller:
Your controller should hava action like below:
public IActionResult Faq()
{
return View();
}
So when you would hit https://localhost:7246/freq_asked soon it would read the defination from route pattern and reroute to your expected route.
Output:



Note: Keep in mind whatever you would be written here in pattern: "freq_asked" that would be your URL path. Please refer to this official document if you want to study more.