Welcome to the boat mate.
Env 5.0 is a good mod but when you load any super mod it's gatta go.
TMO has a very good environmental mod in it.
I wouldn't start with a career but use the war patrols for school missions.
Just save at first contact and keep replaying the saves to get some plotting, tracking, set up and shooting practice. Try after mid '43 and you'll have radar, makes learning much easier.
Magic