All units, that can be derived from garmins native user settings are derived from there, so change your user settings to enable 12h/24h mode and/or to use metric/imperial units.
To find out how to change this, here is e.g. the garmin manual for the fenix 6 models explaining how to change the 12h/24h mode on this watch: Link
Following units and settings are derived directly from the watches user settings:
Garmin does not have any native pressure nor wind speed values, so change those 2 units inside my watchfaces settings directly.