You sound young, or scholarly. I say that because in the real world of work, it takes years of experience to match minimum requirements for anything but journeyman/apprenticeship jobs. Your advice is to be a future proof *person*, which is not something most people can even comprehend, let alone achieve.
Excluding entry level, of course, since that tends to sully your resume. You need to be able to demonstrate that you can do the job - not day 1, but certainly be capable by day 14, and functional at day 31.
The only generic advice you could give someone without knowing if they are capable of learning anything (some people just don't do math, or history, or language, even though they probably could, unless they have some sort of reading or learning disability like dyslexia) is management.
The only other possibility is sole proprietorship, but then you have to have skill or experience or desire, and also have a market. So that's not really future proofing unless your skill set and desire and market are also future proof, which is not the case.
You can apply good management skills to an average team no matter the industry. A lower than average team requires industry-specific skills, but depending on the structure of the organization you may be able to get some degree of mentoring type help, so you know where to focus the managing.
Statistically speaking, you are far better off getting management education and experience, and hoping for an average or higher team, and if it's lower than average hoping you have enough experience to cope. And that's about as future proof as you can get.
First layer of non-managers gets laid off? Someone needs to manage the robot supervisors. Robot supervisors get automated? Someone needs to manage the supervision techs.