Question from a non JW

For converts: do they actually tell you outright that once you're baptized you will NEVER ever celebrate another Holiday again? Do they absolutely make it clear that you are expected to NEVER accept a blood transfusion for yourself or child/spouse? Do they tell you all about that Memorial and how you'll be in trouble if you actually eat the bread and wine?

If so, how did they explain that in such a way that made it seem like, "sounds, good, I'm in"