Y is my bill so high
Without knowing what you are paying, how many lines you have, what plan you have, whether or not you are making any device payments for phone purchases, what phone(s) you purchased on payments, whether or not you are paying for insurance, etc... NO ONE would be able to answer your question with any kind of accuracy.
For example, the monthly payment on a 256GB iPhone 11 Pro is $47.91/month. If I were to add THAT to the monthly cost of my phone service, I would also think my bill is high. If I were to add 4 of those phone payments to my 4 line account, I would think my bill is REALLY HIGH!
Knowing ONLY the information you have provided, the answer is that your bill is so high because of the goods/services YOU have chosen to purchase from Verizon. If you want to lower your bill, you can either change the services YOU choose to purchase(i.e. phone plans, insurance, etc...), choose to purchase less expensive phones with monthly payments, don't purchase phones from Verizon on monthly payments or purchase your phones from somewhere else.