Please help: sponsoring process

Hi there. I was requested my passport for visa issuance after almost 2 years of process. I am planning to land in June. I have had a girlfriend for a year and I want to marry her (after landing of course).

I didn't include her in my application because I started my application process before I met her and later when I had already met her, I was advised that it was better to continue my application by myself and then sponsor her. I have a couple of questions:

1.- How long should I stay in Canada, after landing, to come back to my home country and get married? I want to return and get married as soon as possible (hopefully right after getting PR card), but at the same time after an appropriate quantity of weeks/months to start the sponsorship process without any problems or delays.

2. Is it possible that she can come with me at the time of landing (with visa visitor for her) and return to our home country together to get married and then I will return to Canada by myself to start the sponsorship without affecting this process of sponsoring her?

I will appreciate any help of seniors or people who have had this kind of experience.

Thanks so much.