Many people are a little ambidextrous, if you are right handed but favour your left hand for anything then you qualify as ambidextrous. Of course the term is usually given to people who can write equally well with both hands.
You are always using both sides of your brain so it’s not strange for you to be right handed and left footed, some people are just much better at using either side of their brain for fine motor skills. If you could kick a soccer ball equally well with both feet then you could call yourself ambidextrous, although kicking a ball is a lot easier to do with the wrong foot than writing your name is with your wrong hand.
So no you are not ambidextrous is you are right handed but left footed, even though you’re using different hemispheres of your brain, you’re still using different areas within those hemispheres.
