The blower motor (which is brand new 1/2hp) will not start unless I turn it by hand.
It appears to be the capacitor, but I have no idea what the capacitor looks like or where it is located. Can anyone help please. Much thanks

Here are some pix of cap's. Follow the 2 brown wires from the motor to the capacitor. If this is an ECM motor you have a whole different problem.
https://www.askmehelpdesk.com/heating-air-conditioning/heating-cooling-maintenance-repair-troubleshooting-frequently-asked-questions-58313-2.html#post269065