Views and Panels URLs
When you select a Views "Page" type display, it must have a URL. And that URL is where this page will be accessed from.

There's a separate views display that's dedicated to be inside Panels, and that one is called "Content Pane" display inside views. This display doesn't take URL, but also has a lot more options for panels configuration such as argument input from panel, settings overrides such as pager, fields, items per page, base URL etc (need to explicitly allow each from the Views display "Pane settings").

So to answer the question, either use Content Pane display, or you can also use a Block display (as suggested by @JayendraKainthola) which is less flexible inside panels.

Once you've created the display Content Pane, it will be available in the "View panes" category when you're adding it to the panel.