Optimise Contact Form UX

Dear Divi Helpers,

I would like to optimise the UX of a contact form I have created https://sailover.net/contatti/ (sorry, website is not yet in EN)

The issues I would like to address are:

1. In the 3rd field (1st in the second row) I limited the number of number /characters it is possible to enter. Can I attach a message to the field in case people try to enter more characters? Is it possible to attach a similar message to any field where the user is entering wrong characters?

2. If the user tries to send/complete the form with some fields not completed Error Fields become red but the browser stays where the user is. Is it possible to put a sort of anchor to make the browser jump to the top of the form?

3. Is it possible to customise consequently the message to support the user filling correctly the form once the browser jumps on top of the form? At the moment a notice appears there saying which fields must be completed but the fact that they are in grey doesn't make it visible and I would like to customise the message itself.
Example message:
Compila i seguenti campi:
- Ospiti a bordo

I would like to make it red with this line of css
.et-pb-contact-message {
color: #fd4747; }
but this makes also red other elements.

4. If the user tries to complete the form without accepting the first of the two acceptance values needed there is no error message saying that he/she needs to check the box. Is it possible to add it and customise it? For example, adding a message above the field making the same jump described above.

thanks a lot in advance!


Just so you know I also thought it could be better to make the error in the field a bit thicker:
.et_pb_contact p .et_contact_error {
border: 3px solid red!important;
}