WordPress 5.1 and Php 8 Problem

My Website Hoster updated the server to Php 8 where I’m running my WordPress Site with version 5.1 which is not compatible with it. That causes I think following failrues and I cant login to Wp-admin.

Deprecated: Return type of WP_Theme::offsetUnset($offset) should either be compatible with ArrayAccess::offsetUnset(mixed $offset): void, or the #[\ReturnTypeWillChange] attribute should be used to temporarily suppress the notice in /data/web/1/000/066/257/271536/htdocs/wp-includes/class-wp-theme.php on line 493

Warning: Private methods cannot be final as they are never overridden by other classes in /data/web/1/000/066/257/271536/htdocs/wp-includes/class-wp-session-tokens.php on line 69

Fatal error: Array and string offset access syntax with curly braces is no longer supported in /data/web/1/000/066/257/271536/htdocs/wp-includes/script-loader.php on line 706

Are there a solution for this Problem?

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