Projecting face into another

hello guys , i’m trying to do some energetic analysis , and i have in my ifc building walls that are contained in many spaces . but i need the coordinates of just the portion of wall contained in a space .
i thought of projecting vertical faces of space and project them into the wall external face , so that i have one face extracted

can you help in how to do an orthogonal projection of a face into another?

i need this urgently please
Thank you !