This is so true. Also, young cousin, a typical benefit that I know people miss when going full time. If your job offers a 401k with a company match, make sure you put in at least the minimum required to get the full company match, otherwise it’s just free money you’re missing out on. As you get to be older, you’ll appreciate younger you for doing that.
Some other advice regarding 401ks (this is just my two cents). Go for funds with low expense ratios. Typically these are index funds which are great since they are quite diverse (s&p 500 is always a good choice imo). A target retirement fund is also a good idea as they switch investments to less fluctuating investments the closer the target retirement year is.