You realise it's not at all guaranteed, right? You have to pass the OCS first.
Also, it's not recommended to go into the army, then to college, then to the army again because you may never return if you don't meet standards or come back with mental or physical disorders.
But if you're happy being paid a lower wage than a bin man for 4 years, then *shrug*.
Bin men get free dental and healthcare.