From Longman Dictionary of Contemporary Englishgive onto something phrasal verbFRONTif a window, door, or building gives onto a particular place, it leads to that place or you can see that place from it the garden gate that gives onto the main road a small balcony giving onto fields → give→ See Verb table
Examples from the Corpus
give onto • Occasionally they give onto a wide balcony that overlooks the sea.• Put against open window giving onto garden full of trees and it is one thing.• Those on its northern side had ample yards or gardens abutting Great Prescott Street, which itself gave onto Goodman's Fields.• The soldier bolted the door which gave onto the platform and sat down opposite me.• The other side of the hedge gives onto the road. 