relative distance and right ascention The redshift-distance relation is $cz=H_0d$. So if we have $z$ we can calculate $d$. But is there a way to calculate or covert or write this $d$ in terms of right ascension (RA) and declination (DEC) ?

Thanks in advance
No. If you only know the distance to your object, that tells you absolutely nothing about where it is. That's like saying, I know the grocery store is 5 miles from my house, how can use this information to figure out exactly where it is? The answer is that you just can't, you need more information. – zephyr 

In 3D space, you need three coordinates to locate an object. Ra, Dec are two (position on a sphere), z (or some other radial distance measure for nearby objects) is the third. Astronomy usually tries to make do with just Ra, Dec because that's easy to measure. – Alex

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