Legally you cannot have two DLs, nor is it wise to do so as the IRS and the CRA consider a DL a residential tie, so if you have a DL in Canada and the US technically you could be taxed twice if they found out about it.
Nevada is really tough on issuing DLs to anyone, more so for aliens. They don't even recognise DLs issued by States that have less restrictive standards than them, so if you have a Texas DL, they expect you to take the test all over again.

