Premiere show and work ever with 8 bit project, only if you enable high bit depth processing you can see or render out with all bit depth (no comment).
To preview bit depth you must go to menu / sequence / sequence settings, and enable in panel opened "maximum bit depth". this option allow you to see correct preview of 10bit, later when you want to export remember to enable "maximum bit depth" ALSO in export panel or you preview in MBT but render out in 8 bit...
anyway check davinci resolve, is very better option to edit, vfx, color, manage your movie.
Premiere show and work ever with 8 bit project, only if you enable high bit depth processing you can see or render out with all bit depth (no comment). To preview bit depth you must go to menu / sequence / sequence settings, and enable in panel opened "maximum bit depth". this option allow you to see correct preview of 10bit, later when you want to export remember to enable "maximum bit depth" ALSO in export panel or you preview in MBT but render out in 8 bit... anyway check davinci resolve, is very better option to edit, vfx, color, manage your movie.