How To make Custom Links Without Showing page not found error [duplicate]

I want to make custom links to my website without showing page not found error. all links will show same webpage without redirecting.

As example my website is samplewebsite.com. i want to create custom links like samplewebsite.com/123 and that link must be show the samplewebsite.com interface without redirecting.

can i use htaccess to this ? and how ?