Right word

Mister MicawberGood luck in the next step of your life.

Thanks, teacher.

What about here:
What is the next step 'in or of' your life?
Here is how you should plan the next step 'in or of' your life.

For some reason, 'in' sounds better. Am I right or wrong?

Anonymous'in' sounds better. Am I right or wrong?

They sound about equal to me.

Mister MicawberThey sound about equal to me.

I see, So do you mean that both, in and of, are possible in the last two?

If so, would 'in' also be possible in the first original question?

AnonymousSo do you mean that both, in and of, are possible in the last two?

Yes.

Anonymous would 'in' also be possible in the first original question?

I didn't like the two 'in's.

Mister MicawberYes.

Got it.

Mister MicawberI didn't like the two 'in's.

Yes, I agree. I think it sounds not good with the two 'in's.

Can another word be used instead of the first 'in',maybe 'with' or something else? Is 'on' wrong or just not as good?

Then use 'with'
'Good luck on' carries sarcasm. ('With' does, too, but less so.)

Mister Micawber)QuoteThen use 'with''Good luck on' carries sarcasm. ('With' does, too, but less so.)

If I were to use one, I will use the one you suggested, but these question are just for my knowledge. Thanks again!