Apparently because you are missing some basic knowledge and failed to mention it.
Consider changing up your attitude.
In the cases above most everything was referring to a path. A location.
"Where is the file I downloaded? - Its in the Downloads folder.
“Where is the downloads folder?” - In your home folder.
“Ok but where is it really”? - We would express this like: /home/ditendra08/Downloads
(also note ~ is shorthand for /home/ditendra08)
So in the case above we were referencing the desktop file (the one ending in .desktop that is located inside the ‘applications’ directory, within the ‘share’ directory’, within ‘usr’ directory, from root, or ‘/’
The other thing mentioned was cp which is a basic tool for copying.
As with most things you would get that kind of information by using something like
cp --help or man cp
Or really any sort of ‘introduction to linux’ guide or a quick search engine query.
We did. Its not our fault you dont understand.
With it spelled out … do you understand now?
Copy the file from one location to the other and edit it to launch using the desired profile.
(I dont use vivaldi … so you would have to verify its syntax)