What are the differences between metoprolol and propranolol? which is better for treating hypertension of 150/100? what dosage should i take?

No need: to be specific, it gets down to preferences: I prefer cardio-selectives = beta 1 like metoprolol (personally I prefer Bystolic), but sometimes nonselectives= beta 1 & 2) like propranolol are preferred

Metoprolol is better: Metoprolol superior to propranolol for BP. It has better pharmacokinetics and therefore longer lasting in bloodstream to effectuate more consistent BP control. Typically twice daily dosing needed. Having said that, however, drug of choice for BP control, if no other reason for beta-blocker needed, ace inhibitors are an even better choice. If there is end organ damage already, Ace reverses that.