If my friend has control of his grandmother’s house as per her Will but his dad is selling it without his consent, is there anything that can be done?

If your friend believes that his father lacks the authority or power to do this, based on what is in the will, then he could potentially get a court order (injunction) preventing his father from selling. (This involves bringing a legal action--lawsuit--to get the order.) He obviously would want to do this *before* the sale occurs, since if the sale goes through and the house is bought by a good faith purchaser who had no knowledge of the irregularity, the courts would not undo or set aside the sale--the house will reamin sold, though in that case, your friend would seem, based on what you write, to have a claim for compensation against his father. Your friend should consult with an attorney right away, bringing a copy of the will and any other documents in his possession in relation to the house, to evaluate this option.

The above answer rests on the following assumption: presumably, your friend's grandmother has passed; a will only takes effect on death, and if she is still alive, the will has no power at all. If your friend's father otherwise has the power (such as through a POA) to sell the home, then he could even if the home would go to your friend after his grandmother passes away.