Transferring data

Hello,
i am having trouble and hopefully someone can help me i am creating an invoice system for the company i am working for and i have created a source sheet (job name, customer #, payment, Etc.) my goal is to create an invoice where all i have to do is use a drop down box to select the job number and the rest of the information will automatically follow (i have it set up in rows on the source sheet) i have created the invoice and i can get each box to transfer but i do not know how to get all of it to transfer using just one box any help is appreciated i do not have the best knowledge of the commands yet so very detailed instructions would be great thanks