open onto something
open into something

She wasn't ready to open that door into her own heart.

The door opened into a big room full of light and people.

At great risk, I opened the door into my room.

The first door on the left opened into the common room.

To the left, the living area opened into a small kitchen.

They found a door that opened into a side park.

It opened into the room where the old woman was sitting.

Nor, so far as anyone could know, had the door ever opened into the outside world.

The light, he saw, came from a door that opened into the living area.

Finally, a door would open into a place you recognized.