is it necessary to take both tickets ( up nd down) in the same airline?

Not required...
The coming by one airline going by another airlines...its ok...
Foe example coming by Oman air going by Qatar airways

any issues if we took tickets in different airline??
No issues

If anybody have idea about this, Please share the details.....
So uch experience..my bro is coming today aswell..my cousin bro came last week