The new season is about to begin and even on Clubhouse.tv during their livestream of EPL football the jockeys were hyped about the F1 2023 season. Mentioning about it's start the cars will go through in week from now with testing in Sakhir.
Then a week later the new season will commence in Bahrain.
Here are the testing and planned schedule for season 2023:
https://www.formula1.com/en/racing/2023.html

If you want to watch a preview of what to expect in the testing I found this informative video (rather short compared to all the rest I have viewed) and what the cars that were previewed should have changed during the testing.
F1 2023 Pre Season Test Preview and Predictions by MrPulse
https://www.youtube.com/watch?v=DjuO1JIk1qs

Such as the red bull car that was unveiled in New York the past week was actually the 2022 seasons with slight changes.
But during testing they should have a much different looking car out there instead.

https://www.formula1.com/en/latest/article.first-look-red-bull-reveal-2023-rb19-during-spectacular-new-york-launch.4iN7zpmadjkx9wDqvONMWR.html