Can you switch branches of the Military?

I have already signed my first initial contract to be an intelligence op but be reservist. I have not been to any trainings and I havent gone to basic training yet. Just signed contract after MEPS. I would Like to switch to the Navy and go full time. I discovered the Air force isnt what I wanted. especially not... show more I have already signed my first initial contract to be an intelligence op but be reservist. I have not been to any trainings and I havent gone to basic training yet. Just signed contract after MEPS. I would Like to switch to the Navy and go full time. I discovered the Air force isnt what I wanted. especially not reserves. Could I back out and switch branches? My job requires a top secret clearance would they wipe my clearance or make me pay??
Update: side note *** Im in the delayed entry program
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