installing & upgrading backport package & upgrading system

[jindam, vani]

* i want to install lo package from bullseye-backports.

* correct method for before installation 
of backport lo package? :
(1)
sudo apt -t bullseye-backports update && 
sudo apt -t bullseye-backports full-upgrade
sudo apt -t bullseye-backports install lo

(2)
sudo apt update && sudo apt full-upgrade
sudo apt -t bullseye-backports install lo

* for upgrading entire system after 
installation of backport lo package? :
(1) 
sudo apt update && sudo apt full-upgrade &&
sudo apt -t bullseye-backports update && 
sudo apt -t bullseye-backports full-upgrade

(2)
sudo apt -t bullseye-backports update && 
sudo apt -t bullseye-backports full-upgrade

regards,
jindam, vani

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