I'm not too familiar with the stock game because I play TWoS where all these stock 'tutorial missions' are skipped, and my response above is based on that.
For the stock game: IIRC you must end all these tutorials and also all missions in the captain's log should read 'accomplished' or similar.
When you finish all tutorials, you should have 'unlocked' all torpedo functions, the mini-map, the tools for the map. Look at the upper screen: are there still tutorial icons? If yes you did not finish them. Do so by repeating the instructions (even if you sunk some ships before, the game doesnt' care too much) and then try to dock once really ALL tutorials are 'technically' finished.
If still you have problems, click on the
Search icon here above, chose
Advanced search, enter 'mission' in the search text, chose
search in titles only and for the generic SH5 forum, you will find lots of people complaining not being able to finish 1st mission. You should get your answers there, I know there is a solution.
Then: For the longer term I advice you to read about TWoS and how it changes the game, most players find the stock game too buggy anyway and play with that. I can not judge this however, I remember I did play the tutorials in the stock game but not to the end, and then for some 'good' reasons I switched to TWoS. And I surely won't switch back to the stock game anytime soon...
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Here's a trick to skip tutorial missions (should also work in the stock game):
You can skip the initial tutorials that you must do in every campaign start by editing the file CarrerHistory.cfg in the savegame folder C:\Users\...\Documents\SH5\data\cfg
Just replace the following:
HasCompletedTutorial=false
Change this into:
HasCompletedTutorial=true
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Problem is: you cannot edit every so often the files every time you find a bug or malfunction...
But at least, this should get you started...
I hope you get responses from more competent players, there are some very good veterans here on this site!