Check out the documentation, this will be your best bet on "how to" perform the upgrade.
https://docs.kentico.com/k11/installation/upgrading-to-kentico-11
Short story is you will need to upgrade in these steps as each major upgrade does not include the previous version upgrades:
8.2 -> 9.0
9.0 -> 10.0
10.0 -> 11.0