At the start of your turn, you regain your Reaction and your Free Reactions.
Reaction
You have 1 Reaction per round. Abilities that state “use your Reaction” consume this. Once spent, it is unavailable until the start of your next turn.
Free Reactions
Some abilities are designated as Free Reactions. Free Reactions do not consume your Reaction, but each Free Reaction has its own limit on how often it can be used per round. Using a Free Reaction does not prevent you from using your Reaction, and vice versa.