Indoc period isn't that harsh, though care packages would definitely be helpful for your child to boost spirits and also make friends (sharing). NAPs will provide everything, but I would recommend having underarmour tucked away somewhere as you will do a lot of running.
During the year, I found that having a bike was very useful to get around base and the town of Newport, but its certainly not a necessity.
Apart from that, I don't recall NAPs giving any financial guidance or training. Unless your child is prior enlisted, or you have an existing bank account from your previous work, the navy will sign you up with a bank account at navy federal or USAA. Since almost all of your expenses will be paid for, try to save as much cash as possible throughout the year. When you get to the academy, you will only see a small portion of your pay each month in your account as the majority will be witheld to accommadate for laundry, food etc.
It is also a good idea to have auto pay set up if you have bills that will need to be paid. During Indoc, you will not have a lot of access to internet so if you need to pay bills, it could be an issue.
