WHOA... if this is a 3phase to 3phase inverter DONT CONNECT IT to a single phase supply.... at best it wont work, at worst some magic smoke might escape.... it should say LNE or at least LN if its a single phase in.

On your other questions....

Yes 1,2,3 are UVW and the order doesnt matter. If the motor runs backwards swap ONE pair around.

Breaking resistors are nice to have but not needed. They slow the spindle down after a stop command quicker, esp at the higher speeds, but its something you can live without. As to the value, you'll need more info, guessing could damage the VFD. The value is normally specified in the inverter manual. Typically around 100ohm but too small and you fry the inverter. The wattage rating is typically 10% of the motor rating. See here: Inverter Drive Supermarket | Brake Resistor Calculator for more info, scroll to bottom of page and read the info there first before trying the calculator, then decide its a nice to have for now :)