Hello Angelos,
{ I do not work for JoomShaper }
Just out of curiosity, if you set your System / Global Configuration --> Server --> Error Reporting of Joomla 5 to None or Simple do you still get those deprecated messages and is the rest of that page without the messages showing appearing as expected? If so, leave it at Simple or None until JoomShaper has a chance to fix that template to be 100% PHP 8.2 compatible.
Often you will have Error Reporting to System Default or Maximum you will have those messages appear - NOW do not misunderstand me, I think that JoomShaper should (and will) fix them but in the meantime, if using Simple or None makes the situation go away on the front end of your website that's a nice bypass...
Cheers,
E.