Ok appreciate that hence the "silly question" comment.
On your new watch, there are far more options than there used to be.
On the Watch (and again I'm going up temper this with silly question" but please go to settings, notifications and ensure notifications are turned on there.
Then go to the apps on the watch and again ensure that notifications are turned on.
I am not employed by Samsung nor do I receive any remuneration as a Samsung Members Star.
My device is an S25 Ultra.