I don’t have the CBT access, however I found some issues and bugs from the videos that were posted online, Is there a way to report that?
I don’t think you can report bugs without having an in-game screenshot and the game log files from the match.
If you encounter any bugs yourself then you can bug report it here (just search a bit first so that you don’t report something that is already reported and known about): (Gaijin.net // Issues)
A guide on how to report bugs can be found here: ([Navigation] Technical Knowledge Base | War Thunder Wiki)