In my own experience, which I'd recommend you disregard if it isn't useful for you.
Try lots of things, see if something sticks, it might take years, or decades, but the variety of trying many things is interesting in itself.
Try to connect the dots in your own life, for example what were you like as a kid, what interested you, has any of this followed into your adult life, what about looking forwards e.g. where do you want to be 30 years from now and can your current or new interests get you there.
Having kids will certainly give a person purpose and eat up all of that free time if that's in the plan for you.
Try lots of things, see if something sticks, it might take years, or decades, but the variety of trying many things is interesting in itself.
Try to connect the dots in your own life, for example what were you like as a kid, what interested you, has any of this followed into your adult life, what about looking forwards e.g. where do you want to be 30 years from now and can your current or new interests get you there.
Having kids will certainly give a person purpose and eat up all of that free time if that's in the plan for you.