Apple averages around 20% net profit after taxes for the company as a whole.
They don’t break out profit for their various product segments, i.e. Mac, iPhone, iPad, Other (Watch, HomePod, AirPod, AppleTV, Beats, etc.) and Services.
iPhone is roughly half their sales. It could be that the other half has net profit of 30% and iPhone is 10%, for a 20% average. Or maybe iPhone is 30% and everything else is 10%, again averaging 20%.
More likely, iPhone net profit is within a few percentage points of the company average.