Hello there I have a unit to install the run is about ten feet long from evaporator to condenser how can I size the pipe

The size of the pipe you use is determined by the size of the fitting opening that is on the unit. Almost all residential unites have a 3/8 OD copper tubing for the High pressure side, the suction side is according to the tonnage of the unit.
If this does not answer your question then let me know.

hello there i have a unit to install the run is about ten feet long from evaporator to condenser how can i size the pipe
Continue with the same size piping that comes out of the condenser and take it up to the evaporator.