Is it normal i dislike my boyfriend's kid?

I know it's prob wrong to say that I do dislike my boyfriend's kid but, there is reasons behind it.
Hello,
I'm a 20 yr old mom whos in a relationship with a 30 yr old man.
I have 2 kids myself from a previous relationship and my boyfriend has his one son from his previous marriage.
Now, to begin with I dont want hate i just want honest opinions and discussions if youre in this situation as well.
At this point im at a lost as to how to feel about it. We are suppose to move in together here shortly.
To start, this kid is obxious he doesnt listen to me at all and my bf just lets it happen weve been in a relation for almost a year and a half now. And at this point he even says i act more like a mother to his son then his biological mother. His mother is a piece of work. She's manipulative toxic likes to say shit under her breath alot of the time. She's mad im with him instead of her when she use to be highly abusive towards him and still has some of those tendencies now.
I can't punish him like i can my kids bc shell throw a bfit about it. So that doesn't help he doesnt care. so when i can i will punish him like he is my own.
One time, he throw a shoe at my face ON PURPOSE and what does my bf do CUDDLE HIM LIKE HE JUST GOT ASSAULTED WITH A SHOE WTF?
He told him to apologize that's it. No whoopin No time out No hand slap nothing just sat on the floor with and let him have a screaming fit for 30 mins and by screaming fit i mean blood curdling screaming for 30 MINS. because i screamed at him for throwing shit.
He whines literally about everything and at times i ignore the whinning bc i gave him what he asked for like i do my own kids unless there is truly an issue. but he asked fro something i give it then he magically wants something diff. im not play 20 mins snack roulette with a 4 year old NO.
he gets mad at me for ignoring him and says im just like his mom which baffles me when this grown ass man cant keep clean after himself.
He spoils him rotten all the time no punishments. if there is a punishment a min of the kid crying he immediately comforts him but if i do that to my kids i baby them wayyyy to much. like common man. You tell me to stop babying them but turn around and do it to him like nah so i disregard everything he says about parenting my kids bc its bs he does the same shit to his.
i dont know what to do anymore im on the verge of losing my shit of this situation bc its a lose lose.