Most Welcome :)

I’m glad that your 404 page error issue got fixed.
Your header issue is resolved now. Actually you did not translate your menu from Appearance >> Menus. But now I translate your menu “Top Bar Right” in arabic and create the same menu for arabic and it gets fixed. Because you did not translate that menu before that’s why it shows category menu as default in the top bar.

Screenshots for clarification about arabic menu: https://jmp.sh/NBsDVPw

Result with English Language: https://jmp.sh/tn8eD0J

Result with Arabic Language: https://jmp.sh/EyQfdvI

You can check your site after clearing your site and browser cache.

Best Regards.