Anyone looking to retire early (especially millennials) always take advantage of your 401k if available or have automatic deductions to a Roth IRA. Even if just $25 a week or month it adds up and you can retire in your fifties. As pay increases, up your contributions. I’m 56, worked a good blue collar job and just hit the $2m mark. Einstein said the 8th wonder of the world was compounding interest.
Good luck and sounds like you had good teachers. Best other lesson is don’t panic when markets are down. Look at it as an opportunity to by quality stocks at a discount.