Hello,

To control the width of the Form Inputs, you can try using the following Custom CSS on your Site and paste it to Dashboard >> Theme Settings >> Custom CSS >> Custom CSS for mobile section:

.mc4wp-form-fields input {
    width: 50% !important;
}

Regarding the text above these fields its width is already set to 100% under the Elementor editor on your Site.

Please check back your Site after completely clearing the browser and server cache.

Best Regards.