French phrase
Si vous voulez, je peux ~.
Meaning
If you'd like, I can ___.
When to use it
A polite way to offer help or another action. It leaves the choice to the other person.
Example dialogue
Si vous voulez, je peux vous aider.
If you'd like, I can help you.
Merci, c'est gentil.
Thank you, that's kind of you.