To apply for a US work visa from Canada, you must obtain a valid job offer from a US employer.
You can follow the steps below to get a US work visa from Canada:
Step 1: Get a job offer in the US
Step 2: The US employer files a petition with the USCIS
Step 3: Choose the US work visa type based on your purpose
Step 4: Apply for the work visa
Step 5: Await the visa status