Landlubber Noob in need of assistance! :)

[Finnbat]

Yes, you are right.
You need to get hole under waterline.

[kylania]

The Grey Wolves mod was not designed with the tutorials in mind, which makes them extremely difficult compared to how they would run in Vanilla SH3.

You don't actually need to complete the training missions, and in fact the only reward you get will be quickly gained after your first career patrol.

If you feel confident using the deck gun, and realize how difficult it is to sink anything larger than a few hundred tons with it, you should consider the training mission complete and useful.

Grey Wolves, and other "supermods" like NYGM 2.2, certainly makes SH3 more difficult but it adds so much to the game and being successful on a patrol where you knew real risk is much more of a reward than a few quick explosions.

[Dantenoc]

edited: nevermind... Kylania already answered