I want to know if I need a 1098T form if I have school expenses, but I am technically employed by the Navy?

People who are employed and going to school part time are still eligible for the credits, as long as the scholl you attend is an eligible institution*.  

Military Training, even formal classroom training, is not an eligible school. 

* To be eligible for the tuition credits, the course must be taken at "an eligible institution". The school should be able to tell you if it is an eligible educational institution. In general, an eligible educational institution is an accredited college, university, vocational school, or other postsecondary educational institution, including accredited, public, nonprofit, and proprietary (privately-owned, profit-making) postsecondary institutions. Additionally, in order to be an eligible educational institution, the school must be eligible to participate in a student aid program administered by the Department of Education. If they issue a 1098-T they are probably an eligible institution.

Enter your school at the link below, to see if it's on the dept. of education list.

https://ope.ed.gov/dapip/#/home

A form 1098-T was made a requirement for the education credits a couple of years ago.  However, if you qualify for an exception, you may still claim the Credit, without a 1098-T.  If you attended an eligible institution, you most likely qualify for an exception. 

 “However, a taxpayer may claim one of these education
benefits if the student doesn’t receive a Form 1098-T because
the student’s educational institution isn’t required to send a
Form 1098-T to the student under existing rules (for example, if
the student is a nonresident alien, has qualified education
expenses paid entirely with scholarships, or has qualified
education expenses paid under a formal billing arrangement). If a
student’s educational institution isn’t required to provide a Form
1098-T to the student, a taxpayer may claim one of these
education benefits without a Form 1098-T if the taxpayer
otherwise qualifies, can demonstrate that the taxpayer (or a
dependent) was enrolled at an eligible educational institution,
and can substantiate the payment of qualified tuition and related
expenses.”  https://www.irs.gov/pub/irs-pdf/f8917.pdf