Feel lost after achievement

Spent my 20s going to grad school, taking endless number of certification exams, becoming mid level manager. Now in my mid 30s. Feeling super lost in terms of "what's next?" Job feels boring, and I feel like I'm living a life that has no big purpose. I tried to set up new goals like getting super fit, learning Spanish. I still feel these goals aren't significant enough for me to feel like I'm headed towards something. Idk if I'm having a mid life crisis or existential crisis. I am single and while I do enjoy going on dates and consider the idea of getting married and having kids, I don't feel I'm ready for it.

I thought maybe I need hobbies but to me I see hobbies as hobbies, not something I must grind for serve a big purpose.

I'm now just rambling. Sorry about that. I just feel lost with life.

I'd appreciate any help.