yung form 80 is 'Personal particulars for assessment including character assessment'. It provides detailed information of applicants enabling DIBP to make a sound decision based on facts that an applicant has made. So dapat consistent ka sa mga entries na binibigay sa DIBP. Tinatanong dito yung Addresses mo for the past 10 years, movements/travel mo, education etc etc.
Yung application form kasi ng PR naka embed sya sa site unlike itong form 80 na to, pwede mo sya iedit as pdf then print, sign then scan ulit. Tapos iuupload mo sya upon lodging. Parang ganito yung steps for you to understand it further. First of course, creating an immi account. When invited by Skillselect, click mo lang yung link, which would eventually lead you to the application process. Andun yung embedded na form for skilled migration. After nun, payment. After ng payment, it will let you upload up to 60 docs per applicant if I'm not mistaken. Be sure pdf, bmp, jpg, gif etc mga format mo and not exceeding 5mb per document. Dun mo na din iuupload yung form 80 and everything na pwede mong gamitin as proof na you are really eligible for migration. That's you proof of identities, educational backgrounds, police checks, previous employments, marriage cert, licenses, etc.