Immigrate to Canada and then go to America.

There should be two forms here: you can apply according to your own specific situation;

First, you can apply for visiting relatives directly after marriage, and you can stay in the United States for 3-6 months at the longest.

Second, apply for reunion immigration in Canada after marriage. After your immigration application is approved, you land in Canada. Then you can get your permanent resident card "Maple Leaf Card" within 45 to 90 days after landing in Canada. When you have a maple leaf card, you can apply for an "American visa" soon according to your situation. Here, you can apply for 1-60 according to your own situation.