Receiving head

So I’ve been told it’s supposed to feel good, but I absolutely hate it. Not talking about with one specific guy that’s like bad at it, I’ve hated every single experience I’ve had with any guy. Is there anyone else that feels the same as me so I can feel less weird for not liking it? Maybe the guys I’ve been with have just sucked at giving head? Like how is it supposed to feel? Maybe if I knew how to do it I could guide them to make it feel good, but it’s not like I can practice on myself and then tell them. Is there a kind soul out there that could explain to me how to orally please a woman? And also, just a general question, how do you tell a guy that you don’t want him to go down on you? Like I’ve tried to just tell them in the moment but it’s so awkward, they’re so eager to do it and then I’m just like “don’t”.