redirection problem and question after moving host

Hello .

Some Scripting expert at Hostmonster (Dreamhost) has solved the issue of home/siteurl for me. Still I dont know what I have to do to guarantee a flexible and proper redirection of search engines / searching people. I am trying to do the 301 redirect thing, but not knowing how.

Old blog was at https://www.al-rasid.com/blog (www.i3tesam.com/iceq/al-rasid/blog)

It is not at cinema.al-rasid.com (tollab.org/al-rasid/cinema)

I want to redirect it to the gate, namely https://www.al-rasid.com (tollab.org/al-rasid/).

Now if I visit https://www.al-rasid.com/blog I am redirected to the site on the new host.

If I however visit a link through Google, which is :
https://www.al-rasid.com/blog/about/what-is-my-blog-about/

I get 404 as you can see.

So where should I place the 301 code, in the old host or the new one? and what should it contain ?

Thanx !