some quasions

Hi,
i have some quasions.
1.as i understand i need to clone my blog to use another lang.
i have website in EN with many posts/images and etc…
if i want to add hebrew i need to clone all the pages and images to the new blog right?

so every time when i will add new page to EN for example i will need to go to HE blog and add the same page right?

or i can manage all in one place?

2. i am using domain mapping so how it will work?
for example, myblog.somewebsite.com now is http://www.mywebsite.com
when i will add another blog,
how can i set that myblog.somewebsite.com now is http://www.mywebsite.com
and myheblog.somewebsite.com now is http://www.mywebsite.com/he/?

https://ww.wp.xz.cn/plugins/multisite-language-switcher/