No. Nokia 5.1 does not have the front camera LED flash but it does have the display screen flash.
Nokia 5.1 has an ARM Mali T-860 MP2 GPU. It is a dual core GPU and GPU frequency is 700 MHz.
Yes, Nokia 5.1 is made of Aluminium metal.
Yes, Nokia 5.1 does have the fingerprint sensor. It is located on the back panel of the phone.