You will not see real time step counts while walking, but you can see summary of step counts at any time on the activity app.
Tap the activity app, (coloured rings) and on the move goal red ring slide your finger up and it will show the steps you have taken.
It will not be up to date in real time because steps are calcuated from the total distance divided by the calibrated stride.
Steps are also accumulated in the Fitness app several times a day on your iPhone.

You can also start a Workout, type Outside Walk, if you have not already found that. It will show metres or yards walked but not ateps.
See this guide
Start a workout on Apple Watch – Apple Support (UK)
Finally there are third party apps like Strava that also show rea time distance but not steps.