Need some help to use altdq and altdqs megafunction.

So you want to make your own memory Phy? Most (if not all) of the top reputation holders will warn you that is a challenge. I too believe it is.

To answer your question: Yes, using altdq and altdqs is one way to go.

Now If you are using altdq and altdqs you are getting near the complexity of Altera's Altmem_Phy.

There are other solutions depending on your requirements on the memory speed and number of chips, or DIMMs, involved.

Is there a particular reason you want to roll your own?