It's generally not recommended to submit the same paper to multiple venues simultaneously, as this can be considered unethical and can harm your reputation in the academic community. Since your paper is still under review, it's best to wait for a decision from the current venue before considering other options.
60 days is not an unusual length of time for a paper to be under review, and it's understandable to be anxious during this period. You could consider sending a polite follow-up email to the editor asking for an estimated time frame for a decision. However, it's important to be patient and not rush the review process, as this can negatively impact the quality of the review and ultimately the acceptance of your paper.
If you do receive a rejection from the current venue, you could consider revising your paper based on the reviewer feedback and submitting it to another journal or conference. It's always a good idea to carefully research the acceptance rates and reputations of different venues before making a decision on where to submit.
Scholars often present results in the form a conference paper AND later follow up with a published journal article, in which case you would add a footnote saying something such as "This research was originally presented at [conference name, date, etc.).
I agree with Ajit that submitting the same paper simultaneously to two sources is not ethical. However, I believe that the same research can lead to more than one paper--one presenting preliminary results at a conference and one, a final version, for publication.
Thank you Donald J. Polzella Ajit Singh for your responses, I got a reply from the journal with major revisions. Do you know how long does it take to review the manuscript after revision? What is the acceptance rate of "accepted with major changes"?
It's rare for a paper to be accepted without any revision. "Major revision" suggests that you will need to work hard on the revision. There is no guarantee, of course, that the revised paper will ultimately be accepted, but it is likely it will be. If the Editor thought the paper would not be inappropriate for the Journal, he/she would have rejected it outright. It is difficult to predict how long this second review will take. It will likely depend on how much changed the revision is. If it were I, I would write the revision and hope for a prompt response. In the meantime, as I said in my previous post, you should consider presenting the results at a conference while waiting for the Editor to finally accept the paper.