Does damage dealt to a planeswalker use the same damage prevention rules as damage dealt to creatures?

Damage prevention and replacement effects (such as those created by spells like Fog, abilities like Shield counters, or the protection keyword) apply equally regardless of what the damage target is — creature, planeswalker, player, or battle. CR 120.4 states that damage can be prevented or replaced by prevention effects and replacement effects, with no distinction based on the type of object receiving it.

When a source deals damage to a planeswalker, the damage is marked on the planeswalker and then, at the end of the damage-dealing step (or immediately for non-combat damage), that many loyalty counters are removed from it (CR 120.3). But before that process even begins, any applicable prevention shields or replacement effects intercept the damage exactly as they would for a creature.

The protection keyword (CR 702.16) prevents all damage from sources with the relevant quality, and this applies fully when the protected permanent or player would be dealt damage via a redirect to a planeswalker as well — though note protection is a property of the object being protected, not the planeswalker itself, so a planeswalker generally cannot have protection on its own unless granted by an effect.

Concrete example: Your opponent attacks with a 4/4 creature and you redirect the combat damage to your Liliana of the Veil. You have a Dazzling Ramparts effect preventing 2 damage from any source to permanents you control this turn. That prevention shield applies: only 2 damage is dealt to Liliana, so only 2 loyalty counters are removed instead of 4.

In short, the rules make no special exception for planeswalkers when it comes to damage prevention or replacement — all the same rules from CR 120.4 and related sections apply uniformly.