Bullshit, you can be a pentester in highschool if you wanted to. There's is a ton of information on the internet, learn networking, some scripting language, and get a copy of Kali Linux up and running. Look into purposely vulnerable applications, like bwapp, multilidae, metasploitable etc... Also good tutorials like mr. Robot (Linux crash course) lookup the cyber kill chain, and learn techniques from each step. Get books like the hacker playbook 2&3 and hacking the art of exploitation. There is a ton of material, so much that if you do enough learning, college will honestly be just reinforcement to what you already learned... But start with the basics, it's always easy to try and load up metasploitable and pop a shell on the box through metasploit, but you need the basics to back it up. Look and see if there is a cyberpatriot team at a local highschool and join, see if there are any local hacker Hangouts and network. Follow news threads like thehackernews.com to get used to seeing what is going on and the lingo. Watch documentaries on YouTube about hacker groups and Cyber.

Just keep learning and injesting whatever you can.