• 1. How much long time it will take to publish a paper?!

Once Author submit his/her paper, the review of the paper will come within 7 to 10 days. then he/she have to send his/her within 14 days. then his/her paper will be published within 1 week.
so typically it should take 1 month from submit to publish unless the paper require major edit/ changes.

• 2. Can i get an extension to give the if there occur some problem to collect the ?

Yes, but author have to inform us earlier. other wise, within maximum 21 days his/her paper will be automatically rejected.