How do Australian students apply for immigration when they marry local citizens?

Marriage certificate is similar to cohabitation without marriage certificate in Australia.

Marriage certificate is not very important, but cohabitation is very important. You need your spouse to have the qualification of spouse sponsorship. You need to provide at least evidence to prove that you have lived together for more than six months. Your spouse must sponsor you before you can immigrate through marriage. You will be given a temporary residence visa after immigration. After two years, if you are not divorced, your spouse will continue to support you. Only if the spouse immigrants have a quota can they get PR.