I am a non us or canadian citizen working in the USA on an H1 visa. I have also applied through my wife to get my permanent residence (which is pending now). I have got my advance parol to travel outside the USA. But I want to use H1B stamp instead of the advance parol

I am going to canada to get my H1B visa stamp for the first time. My questions are

1. Is it safe to go to canada to get the H1B visa stamp?
2. Do I need to tell the US Embassy in canada that I have advance parol and my permeant residence status is pending?
3. If I don't get my H1B stamp from Canada, can I get back to the US using my Advance parol?
4. Do the letter that I got from my company should have the same job title, job description and salary as the H1 application that was filed by my company? I have changed my job title and my salary is also different.

Thank you for your response.

You need to consult with your employer and their attorney.

Can sombody give me a comment based on their experience?

There are many tricky arrangements among sponsors and applicants for employment based visas, both in H and L categories... I'd rather not go in details. This is why I suggested you consult your employer's attorney so that things go as they planned, especially if your visa was arranged by employment brokers.