You have to think this through as a logical adult. If if hurts to pull a bandaid off your arm then it's definitely going to hurt to rip hair off your vagina. I put it in these words so that you make no mistake about it, if you know that you have zero pain tolerance, then a Brazilian isn't where you should start. Consider getting a Traditional Bikini or an Extended Bikini, that way you can get more comfortable with it. and move up from there if you want.
There are two big things that come to mind when you come in your first wax, the anxiety of having your nether regions being stared at by a stranger, and the level of pain you'll experience. So it's really helpful to know that just by following the Before Wax prep, you'll significantly decrease the level of pain you'll experience. The biggest issue I see new clients coming in with is that they don't bother to exfoliate the night before. Having a bunch of dead skin for the wax to stick to is only going to cause the wax to get stuck, and removing it is going to be 10x's more painful than it needed to be.
As far as having someone you don't know staring at you while you're in the nude- you've got to understand that I've been doing this for 20 years. Do you have ANY IDEA how many waxes that is? Even conservatively. we'd be looking at about FIFTY THOUSAND BRAZILIAN WAXES IN MY CAREER. So trust me, not only do I not care what your anatomy looks like down below, I don't even see it to be honest, I'm simply trying to get my job done in the fastest and least painful way!
The other really helpful thing for you to know is that after your first wax, if you come in for your next one withing 4-5 weeks, you'll have a vastly different experience than the first one. You wont be nearly as anxious, and you'll also have less than half of the regrowth than you would've had if you'd been shaving. Not to mention- you'll also have thinned out the texture of your hair as well! By the end of the wax, you'll be turning to me telling me that you barely felt anything at all and you completely understand why so many women make it part of their routine grooming schedule.