How many Healing Cards can Wounded Waters Bleeding claim?

How many Healing Cards can Wounded Waters Bleeding claim?

At most two.
Both Serene Waters and Roiling Waters can only be claimed as a first Healing Card, and both Waters Renew and Waters Taste of Ruin can only be claimed as a final Healing Card.
Though it’s not advantageous to do so, you can skip both Serene Waters and Roiling Waters to fully heal with only one Healing Card, or even never gain a Healing Card at all!