Air Force:
https://careers.airforce.com/how-to-join/process
https://careers.airforce.com/how-to-join/prepare-for-success/meet-requirements
https://careers.airforce.com/careers/browse-careers/
Army:
https://www.goarmy.com/learn.html
https://www.goarmy.com/careers-and-jobs/browse-career-and-job-categories.html
Coast Guard:
https://www.gocoastguard.com/faq/what-are-the-qualifications-to-join-the-coast-guard
Marines:
https://www.marines.com/becoming-a-marine/overview.html
National Guard:
https://www.nationalguard.com/eligibility
https://www.nationalguard.com/how-to-join
https://www.nationalguard.com/careers/
Navy:
https://www.navy.com/joining/ways-to-join/never-served.html#ft-qualifications-&-commitment
https://www.navy.com/careers/index.html
https://www.navy.com/navy-life/transitioning-to-the-fleet.html