Hello, @LMcompany,
1- By adding this custom CSS code in the theme options the header issue is resolved. check the image: https://postimg.cc/Lq0dq3f1
2- With the help of custom CSS code I have set the content to the right side check the image: https://postimg.cc/XGpR910b
3- Regarding the header issue the mobile one appears on the desktop and the desktop one appears on mobile is a cache issue. I can see that your site is loading from the cache and CDN/Cloudflare is activated on your site check the image: https://postimg.cc/D4rVjWpf so in order to solve your issue you have to contact your service provider to flush the server cache and disable the CDN/Cloudflare till you site is in the development mode.
Regards 8Themes Team.