Upgrade theme Classified ads

Hi. I have been told to contact an author about my issue.
I want to change my theme from the old one but it does not work. Loads of errors. Said to probably be a needed update. I use PHP 8.2
Licensee:Orestone Group Co
Item Title:AdForest - Classified Ads WordPress Theme
Item URL:https://themeforest.net/item/adforest-classified-wordpress-theme/19481695
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