No flights are included. Peru Cultural Journeys does not book international flights. We suggest getting your Peruvian national flights (to Cusco and to Lima from Juliacca if you will be going to Lake Titicaca) as part of your international flight booking. That way, if there are delays or flight changes, your complete booking will be recognized within the system and they will be responsible to assist you.
The flight to Cusco from Lima is about an hour. Depending You can either stay overnight in Lima or travel directly to Cusco. Domestic airlines use commercial planes for these flights that offer inflight entertainment and snacks.
You can check your airline, but most internal flights use 727s or similar size jet planes with a capacity of 80-120 passengers. Manu tours use smaller 10-15 passenger propeller planes typically.