You are working too hard, and contrary to popular workflows.
Start a sketch and hide the Origin planes, you will see a sketch Origin point. Constrain to this point. To stick to the x direction, use horizontal to this point.
Projecting the X plane, gives a purple short line that can not be altered unless you beak the link, so why bother, just draw your own horizontal line and it can be any length, and side you need. You probably snagged the mid point of the projected line to constrain that circle.
Small circle, constrain horizontal with centre point, and sketch origin.
Pick Tangent is awkward in Fusion, Dimension > Select circle, right click, select pick Tangent, then select second circle right click, select Pick Tangent, and set distance.
Sketch points on circles for just Dimension, is clutter, and not required, the way Fusion works.
There is no wrong way, just better ways sometimes.
Might help....