How to automate procedure from MRP to P.O and then EDI

hi

can some explain the steps i need to perform if i want to automate the process form mrp run to creation of p,o and the send it to vendor using EDI PLZ

donno much about mrp so if some can explain in easy steps i want

mrp run and generates p.req

i have source of supply so p.req will pick one of them

then automaticlay create p.o and then using message type neu send it to customer

how can i run mrp on spaceifc material so it can generate a p.req and then p,o

thank you very much gurus