il suffit de demander
If you want me to help you, all you have to do is ask.
Si vous voulez que je vous aide, il vous suffit de me le demander.
If you really want to know, all you have to do is ask.
Si vous voulez vraiment savoir, il vous suffit de demander.
All you have to do is ask him to pay the debt.
Il vous suffit de lui demander de rembourser la dette.