Do I have a right to eat dinner by myself I am 11 years old my mom always wants me to eat with her what should I do

Eat with her.
It is one family thing worth holding onto since families already have very little family time together these days. Someday you will look back and be glad you had set aside a specific time of day for mom.

Sounds like you're a little not happy around your mom right now. Maybe you can try talking to her about the things that have been troubling you so you can join her and eat like a family. Also, she's the adult, so if she says you have to, then you do. I think that you are upset with her about something. Why be upset with each other when you don't have to. All you have to do is talk to her about why you're not wanting to spend time with her, (and eat a meal with her) and I think she'll be so happy to hear that you are trying to fix things so she can have you back. Just fix it so you don't have to worry about whether you have the right to eat without her...