conversion

Also...

In 1st step, thats CuI

niely done.. good.

Simply by adding a stronger oxidzing agent than -Br that if -Cl or simply CH₃COCl that is we can add with ether this will bring it in one Step

@ pritish- Mg lagne mein problem toh nahi hogi??

Nahi, I checked, Grignard reagent formation is a very useful route for these purposes. Problem tab hoti hai jab koi substituent ko hatana chaahe via substitution. There is no problem in addition.
The last step works out because magnesium bromide ka ppt banta hai, which shifts the equilibrium of formation far forward.