With the End of Support for LoadRunner v12 on 30 Sep 2022, there have been many companies moving to a supported version.
If you were to open the assets in your current version, and perform any maintenance to ensure a clean test run prior to the beginning of the upgrade process that freezes your testbed, this would give you the best case for your assets to make this migration. Obviously, if your scripts and scenarios ran poorly before the upgrade, they will continue to run poorly without maintenance. LoadRunner 2022 R2 is a wonderful product, but it is not a panacea for bad script design, execution or coding. After all, performance test scripting and scenario design is just a specialized form of programming and subject to all the SDLC rules as any customer facing application.

I'd also recommend this resource: VuGen 2022 R2 Deprecated Features. You'll want to review this for deprecated or removed features, technologies or processes that would impact your current scripts/scenarios. You may also wish to review VuGen Known Issues for information may or may not impact your environment.

Once the environment updates are completed by your installation team, each script will need to be opened in the new version to update the script version from 12.63 to 2022 R2. VuGen will generate a warning about how upgrading is not reversible. Accept that, set the run time settings to a few iterations (2 is enough) and run. There are no changes made to the script as this happens, there should be no need to refactor or recode anything. The changes are updating the engine that drives the Vuser type, and applying them to the script. There are NO code changes made by the migration.
When your script runs as expected Save, zip and send to LRE according to the processes set up in your organization.