First of all, congratulations on being a man and serving your country. You've chosen the higher road, and, whether you find it pleasant or not, enjoy it.
As far as attending college while in the service, it can be done, and there are many routes to get there. The Navy probably won't support any any higher education until you complete your nuclear training (i.e., A-School, Nuke School and prototype). Then, once you get to sea, while available, the chances to make any real progress toward a real engineering degree will be very limited and difficult [Although things might (

) be better now in the internet age (e.g., UT offers a Masters in Nuclear Engineering over the internet)]. It looks like all the information that you're getting right now from the Navy is Pixie Dust and Rainbows. It might be handy to get some real life examples of how it has been done.
Twenty years ago when I went through boot camp in Orlando, the Navy had screwed up the curriculum for A-school and my entry into nuke training was delayed for several weeks [get use to the term "needs of the Navy"]. Because of this, I was put to work digging ditches [manually] with the CBs for a couple of months. Having had about three semesters of college, I went ahead and signed up for some college courses in the evening [as opposed to going out and getting drunk every night like most of my classmates]. That went well, so when I finally started A-school, I continued to take evening classes. Then after A-School, Navy efficiency in scheduling led to another three month delay before my class was to start Nuke school. Well, it was back to digging ditches for three months [I was getting to be a pretty good ditch digger by this point]. So, given the abbreviated two-month semester schedule of the night school that I was attending, I was getting pretty close to finishing my degree. When Nuke school started, I only had a few classes to go, so I pushed on.
Then one day [several weeks into Nuke school] I was walking down the hall in Nuke school and passed this fat old bald dude that was in one of my evening classes [keep in mind that he was probably no fatter, or older, or balder than I myself am now, but in my memory he'll always be a fat old bald dude]. As I said howdy to him, I noticed that he was dressed in a Master Chief's uniform. Well, the next thing I knew I was called into my chief's office where he informed me that it had come to the Command Master Chief's attention that I was taking college classes at night thereby cheating the navy out of study hours that I could otherwise spend studying for my Nuke school classes.
I explained that I had a 3.6 GPA in Nuke school and was meeting all of my recommended study hour requirements. He responded that if I spent that extra study time on Nuke school, I could have an even higher GPA. When I protested that what I did on my free time was my business, he reminded me that you have no free time in the Navy. It all belongs to the Navy. He then gave me a direct order to stop attending my evening classes. So, I spent the remainder of my free time in Orlando going out and getting drunk like most of my classmates.
Luckily though, the prototype that the Navy sent me to in New York [S3G] was broken when I got there [stress corrosion cracking on the reactor inlet nozzle] and once I qualified on everything I could without having the plant operational, I had another four month delay, during which time I completed my degree.
So, it can be done during a six year enlistment, but you'll need to seize the opportunities when you get them, and roll with the punches. I'll tell you this though, I had plenty of friends who spent all of their off duty time drinking and playing Rugby. These guys had a blast while they were in the Navy, and once they got out, they had no trouble at all finishing their degrees within a couple of years. So, if I were you, I wouldn't worry about it too much. Do the job that the Navy gives you to do. Enjoy the time that they allow you off the ship, and pick up your education again when you get out. The practical experience you get will make school a piece of cake six years from now.
Enjoy,
MGM