Microsoft has several tech and customer support phone numbers depending on your country and where you're located at.
The customer support and Tech Support Microsoft Phone Number is 1 (800) 642 7676
1 (800) 892 5234 (TTY)
Be aware of some fake Microsoft Tech Support Phone Numbers that lead to scammers and be aware that Microsoft will not call you personally unless you call them first and request a call back.
If someone calls you claiming to be from Microsoft then hangup because it's not them unless you requested a call back from them.
Microsoft has a page listing all their customer support phone numbers for different countries which you can find at this link. https://support.microsoft.com/en-us/help/4051701/global-customer-service-phone-numbers