I wouldn't worry about it for now. They'll talk about it at OCS (one of many briefs to look forward to), and you can change coverage amounts, beneficiaries, etc at that time as well. Not sure if you are already covered, or if it kicks in when you check in at OCS, or when you sign your papers with the OR, but it shouldn't matter for the time being unless you need to change your beneficiary, in which case you'd probably need to ask your OR for help.
As for term life vs. whole life insurance policies, whole life is good if you can get a relatively good rate. Essentially what you're doing is paying cash into a policy, it grows at a certain rate, and later on you can cash it in. It's usually better than sticking it in a savings account or the mattress, but is not as accessible (or "liquid"). People usually use it for end-of-life expenses, such as to help pay for a funeral, since it never expires, so they'll get like $10k of whole life coverage to supplement a term life plan. Some people also use it for investment purposes and the like.
Term is basically you making a bet that you'll die in the next twenty years (or however long the term is). If you're wrong, no payout. But it's more common than whole life, because payments are much smaller for similar coverage amounts. This is also popular when someone has a lot of debt (mortgage, car loan, etc.) and/or dependents; that way, the significant other and kids don't have to worry about mortgage payments, etc on top of the loss of their loved one.
Like people have said, SGLI is a no brainer, because it's $26-ish dollars per month for $400,000 of coverage with no war clause. I have no debt and no dependents, and I still got the policy, in case I have more of both down the road. You can also start at lower coverage and increase it later on as your situation changes.
