If I was to redo my 20s. What worked was going to university in my mid 20s. I was able to finish it much quicker and made some close friends during by that time as well as set my career path going. What I wish I had done was move away from the city I grew up in. I only did it in my late 20s and I regret not doing it sooner.
Have lots of social interactions. It’s valuable. Set yourself up career wise. Always check to know you haven’t hit a ceiling where you’re working. Exercise and travel lots would be my key takeaways.