Well first welcome to the forums.
Then secondly, this issue has nothing to do with host.
Your themes and plugin is causing the problem.
Disable all the themes and plugins.
Revert back to the default Twenty-Twenty Theme by wordpress.
Check if the issue is resolved. Also please don’t bump here, because you need to wait for a day to clear out everything, or just clear site data, cache and cookies in your browsers to see the changes.
Now I expect the issue to be resolved.
Turn back your plugins and themes one by one and test in the another browser tab.
Once you get your site corrupted again, you will get to know which plugin/theme was the culprit and causing the broken site issue.
Ah in case you are unable to open your dashboard, you can follow my steps from FTP.
In your case, I will recommend you reinstalling wordpress properly again from softaculous.
Also do you have real astra theme?
Also please don’t use nulled content IF using,
Theme might be causing this conflict. Disable the Astra theme using FTP by renaming the folder to Astra.old
This is all really unnecessary. The real fix to the problem is to force https and stop mixed content. It has nothing to do with the themes or plugins whatsoever.