Attaching porch roof or pergola to old brick home
If your brick wall is solid and sturdy, you can through-bolt a wood header the same width as your new porch, and connect the joists to it using hardware for T joint.
Ideally, your posts shall be set away from the house to allow room for good foundations. You can add bracings or diagonals to maintain the squareness of the deck, and to resist the lateral load.