A simple way to represent two ball bearings in this assembly is to put one spherical joint at one end of the cylinder and a general joint at the other end of the cylinder. You should split the face of the shaft and cylinder at the planes where each bearing race will seat. The spherical joint supports 3 DOF. Assume the X axis is along the shaft. The general joint should constrain displacement in Y and Z and leave X displacement free. Normally, you want the cylinder to spin about the X axis, but that would not support a Static Structural analysis with the force you show. So set the rotation about X to 0 while leaving the rotation about Y and Z free.