Hi,
Now i am able to install LaTeX editor and the problem solved by doing:-
Go to your settings → Software and Updates → Ubuntu software, in the dropdown box for "Download from:" you pick a different server.
you change to a different mirror or the main server, then run code:-
sudo apt update
sudo apt upgrade
sudo apt install texstudio
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I think by doing this you will be able to install latex editors like texstudio and texlive-full.
Thanks
Priyanshu