use AWO coupon instead of Virtuemart coupon

I created few coupons, and each coupon is for individual user.

How do I integrate it with Virtuemart coupon , so that VM understands, which coupon to be used for which user.

Hello,

Once you install AwoCoupon, it automatically takes over the coupon system of Virtuemart, unless you altered it. Coupons you created in AwoCoupon should work in Virtuemart. If using virtuemart 2+, make sure VmCoupon - AwoCoupon plugin is enabled.

I wanted to use the coupons in Acymailing.

When I entered the Tag in Acy, a generated coupon was added not the one I added.

Yes, are you using the virtuemart plugin for acymailing or AwoCoupon plugin for acymailing. In either case the coupon will be generated, but depending on which plugin you are using depends where it is generated.