Dimension
Apply and edit a dimensional constraint to control the size and proportions of a sketch. You can make a dimension "driven" so that it's a regular dimension, not a constraint.
Apply a Dimensional Constraint to a Sketch Curve
Constrain the length of a line, the distance between two points, an angle, or the size of an arc or circle.
Edit a Dimensional Constraint
Reposition a dimensional constraint, change the value, make it "driven," or delete it.