On May 2, 8:27*am, Student wrote:
Looking from the inside of our house to the backyard, it slopes from
left to right and slightly back towards the street. We want to build a
leveled stone patio, only slightly sloped for drainage.

Should we excavate the soil to make patio leveled with the lower
grade, or should we build the lower grade up, with retaining walls on
the side? Thanks.

That depends on the heights of what the patio meets
up to, eg the house ettrances, walkways, etc. and aesthetics.
Everything else being equal, it's usually easier to avoid having
retaining walls. Either way, you'll have to remove the topsoil
that is there and backfill with base material.