Location helps!

Most of us put ours in our username so folks don't have to keep asking ;>

If you are asking about a tree to put into the red circle in your picture, unless I have miss interpreted the space, there are nearly no trees that should be put there. You don't have space for a tree like a maple, oak, beach, etc. Most of the flowering trees like cherries, crabapple, etc, will out grow the space. Japanese maples are small, but ones that are about 20 years old will be 15' to 20' in diameter.

SO you choices are limited to dwarf lilacs, nadina, Spirea, etc. and other shrubs that can be kept small.

This is in seattle. yes agree some trees might be too big when fully grown. How about camelia? small, evergreen, beautiful flowers

Not even enough room for a camellia! They will get far too wide for that very narrow site. Maybe something like a Sky Pencil holly or a Wilma Goldcrest lemon-lime cypress

How about one of the decorative miniature conifers? Any of you all have any suggestions for something with yellow new growth and purple cones?