Hello,
01. Navigate to Theme Settings > Styles and Colors> Buttons > In the Advanced button styles section, you can select the Add to Cart button in the dropdown and change the text transform and other font settings: https://ibb.co/zTRdCkcs
Please Follow this guide: https://xtemos.com/docs-topic/advanced-button-styles/
02. Please add below Custom CSS code to Theme Settings > Custom CSS > Desktop CSS:
.single-product .wd-reset-var {
display: flex !important;
justify-content: center !important;
width: 100% !important;
margin-top: 20px !important;
}
Best Regards,