Wedding Website: Creating a RSVP System for Wedding Attendance Confirmation

I'm creating the website for my wedding on WordPress and I would need some customizations. I've finished setting up the static pages, but I'd like to add some functionalities. 1) To access the website, it's necessary to have a Username and Password. I will manually send the access details to my guests. They will use this information to log in. There should be no possibility to create a new username or register independently. 2) If a user loses their access details, there should be a "Request Access Data" button. Clicking on this button will open a page with a form where the user can enter their first and last name. An email will be sent to me, notifying that the person has requested access data. 3) Then, a guest database must be created, and there should be the ability to group selected guests into specific categories (e.g., a group consisting of father, mother, and children). 4) When a guest enters their reserved area, on the RSVP page, they will already see their name and the names of their group members. 5) Below each name, there should be an option to indicate whether they will attend the wedding or not, along with a space to specify allergies or dietary restrictions. 6) At the bottom of the page, there will be a mandatory field to input their email address. 7) Finally, there will be a SUBMIT button, and at that moment, two emails will be sent. One email will be sent to me, containing all the data entered in the form. Another email will be sent to the guest, summarizing their choices. The email will be similar to this: "Thank you for responding to our invitation. You have confirmed the attendance for (number) people." (NAME LIST AND DIETARY RESTRICTIONS) 8) Most importantly, all of this needs to be created in two languages, Italian and Norwegian. Of course, I will provide the text to be inserted.