Hello, Hung,
1/ Have you changed wp-admin access? We can’t log in.
2/ Do you want to delete all current content and install a new demo version?
Please describe your goal in more detail.
3/ Some options were disabled on your site using the White label plugin, for example, https://prnt.sc/8JHxnnvAYJFl , so you can enable them via the settings of the White label plugin.
Best Regards,
8Theme’s Team