is it normal i want to have sex with a horse

you will enjoy it.... you do need to know something about horses. Some horses do not want to be touched
and some enjoy it.... Most likely you will meet a gelding (castrated Male) which is safer than a stallion. Stallions can be really nuts, and dangerous.
Stroke your hand under their tail, gently, and work your way down to the sheath. If they like it, they will start to drop. You can handle it then, and enjoy it. Take it slow, they will tell you if they like it or not. If they start to kick, and back away.... they may not be used to it.... does not mean they hate it... you can try again.... if they just do not like it, and pull up, then they are not happy about it at all. Don't push it... you can get kicked.
If they like it, it is pleasurable. I love the smell and taste, (very strong smegme on the penis and sheath) but I do like that smell and taste. (Some people don't )

Is it normal.... well, for some yes.... as natural as others who enjoy sex with a human. If you are attracted to horses... then it is normal for you (just like all of us who are commenting like this) I never grew up on a farm, and I found myself sexually attracted to horses, and never knew why..... I just was as far back as I can remember. Now with the internet..... tons of us out there. Always put the animals feelings and wants first before yours. Never force yourself on anything.