Yes, Vivo Y17 does have a fingerprint scanner, which is located on the back side of the phone. Vivo Y17 also supports face unlock.
No. Vivo Y17 does not have the front camera flash but it does have the display screen flash, just like an iPhone.
No. Vivo Y17 does not have a dual front camera set up. It has a 20MP front camera.
Yes, Vivo Y17 does have a 3.5 mm headphone jack.