Hello,
Please create separate topics for different questions – https://www.8theme.com/forums/xstore-wordpress-support-forum/
Theme Option > Styling > settings of butttons
Theme Options > Header builder > delete Newsletter element from the header content https://prnt.sc/edQ2in-oSV4a
https://prnt.sc/ZTkKke_sO6DV – contact your hosting provider about this Mixed content issue.
Apearance > Widgets > Header banner > add the static block
If you want to create the multilanguage site you need a special plugin for these purposes https://colorlib.com/wp/wordpress-multilingual-plugins/
Regards