Birthright is a Continuous Trap Card.
Trap Cards are normally Set first and can be activated on a later turn, often in response to an action.
On the current TCG and OCG Forbidden & Limited lists tracked here, Birthright is Unlimited.
YGOPRODeck lists Birthright for these formats: Duel Links, Common Charity, Edison, Speed Duel, TCG, OCG, Master Duel.
A listed print of Birthright appears in Speed Duel: Streets of Battle City (SBC1-ENG18) at Common rarity.
Among markets shown on this page, the lowest listed snapshot for Birthright is about $0.07 on TCGPlayer (prices change frequently).
