This is one way to offer to do something.
This is a casual way to make an offer. It's good for conversations between family members or friends. It conveys the idea that you're letting the person you're talking with make the decision. You may not care, or may not agree. For example:
I can heat up a can of soup if you want.
You can say this to a family member who seems hungry. If the person isn't as close, it's more polite to ask:
Would you like me to make you some soup?