Fiction. Maybe Fantasy. YA/Teenager focused. Read during the 90s. Male protagonist, cover was aerial birds eye view

I'm trying to remember a book that i read back in the 90s as a kid. I probably would have read this around the time I was reading the original Goosebumps from 92-97 ish.

- book for teens/young adults
- fiction. wasn't horror, maybe fantasy fiction
- boy/teenager/male protagonist
- original setting was 90s modern day
- he finds a portal, or something similar
- meets a female that comes out of the portal, or meets her after going into the portal
- portal goes into different world (maybe parallel?)
- he learns new abilities including flight, or something else
(hard to remember the last few points and the rest of the plot)

The cover was
- birds eyes view from the sky (helicopter or plane aerial view)
- looking down at a kid flying with 2 or 3 dogs (maybe more or less dogs, and or different animals)
- the ground below was a mix of green grass patches, maybe crops, some roads etc..

Long shot, but some overlap with Wings by Bill Brittain (1995).

A very long shot; Andre Norton's Witch World?