Welcome to the forum. Please read through the many threads on this forum. Not only are these questions answered but so are many more.
According to the Map at http://www.opencarry.org/restaurant.html, Nevada is green when it comes to carrying at restaurants serving alcohol. Since it's green, you may carry open or concealed (with a valid permit).
According to NRS 202.257, a person may not be in possession of a firearm while under the influence of any controlled substance or with a blood alcohol level of 0.10 or greater. This means it is LEGAL to drink while carrying, open or concealed, so long as you do not exceed 0.10 blood alcohol. Since the DUI limit is 0.08, if you are OK to drive, you are OK to carry.
However, remember, even a little alcohol can impair your judgment, and it is not recommended to "go drinking" while carrying. But on the other hand, I'm not opposed to having a drink or two with dinner. But if I'm carrying, 2 is my strict limit.