I would like to know, that can I file jointly with my wife or married but separated. She is a
Canadian citizen and she does not have a U.S. (SSN). She visits me
Every 2 months and if I round up all her visits she has stayed with me
More than 6 months, so can I claim her by applying for ITIN for her?

And get the stimulus pakage check for both of us.

I have also applied for her visa and if I claim her will there be a
Problem in getting her a visa?

Thanks...

You can file jointly with your wife and apply for an ITIN for her, but the ITIN will make you INELIGIBLE for the stimulus rebate check.

Under a new IRS ruling, you CAN file separately from your wife (puting NRA in her SSN area) and get the stimulus check, then amend the return to file jointly once you get the check.