I've been in for almost 19 years so I don't have any direct experience to draw off of, but my understanding (for the Space Force at least) is that it's pretty competitive. Between most of our manpower requirements, both enlisted & officer, being for space operators & the fact that we're such a small branch, getting into the Space Force as a cyber operator can be tough as far as I'm aware. I can't speak to the other branches, but my best recommendation would be to talk to a recruiter if you're genuinely interested.