How to center align the submit button of the form?

Dear,

Kindly, I would like you to review my first form to help me identify opportunities for design improvements. What else could I do to make it more attractive to get more budgets?

Is there any way to make it better formatted on this page?

http://www.criativaurbana.com.br/pagina/orcamento-de-moletons-e-jaquetas-personalizadas.html

And how can I increase the size of the "request budget" button and center it?

To make better forms, I would suggest you check the "Create Better Forms" section of our User Guides.

https://www.jotform.com/help/chapter-0-How+to+Create+Better+Forms

With regards to centering the submit button, please try to change the button alignment property of the Submit button to center as shown in the image below.

I hope this helps. Please feel free to contact us again anytime if you have other questions or concerns.

Thank you.