Immigration Canada said I had read the documents. How long will it take for the visa to come down?

It depends on what kind of immigration you are applying for. It can be roughly divided into four types: federal investment immigrants, Quebec investment immigrants, federal skilled immigrants and Quebec skilled immigrants. Every cycle is different. Generally, it takes 2 years for federal investment immigrants to get visas, and 2.5 years for Quebec investment immigrants. Federal skilled immigrants for 8- 12 months, Quebec skilled immigrants for10.5 years.

And I wonder if you downloaded the file number. If yes, you can further determine how long it will take.

After the visa comes down, there is a visa validity period and you must land in Canada within the visa validity period. Generally, the validity period starts from one year after the physical examination, and the visa can be obtained within 1-3 months after the physical examination.