There is a lot to know about dog training. Marker words, commands, tricks, dog sports... There is a lot going on; where do you start? Let's start with the easy stuff! Many dog owners know about commands such as come, sit, down, stay, but many don't know that they will also need a release word for their dogs.
Think about this: you're practicing a sit and stay with your dog; how do you tell your dog that you're done with the training session and to go be a dog? A release word is how! You can choose any word that makes sense to you. Many people use "break", "okay", or "free dog". You can pick any word that you like, but you have to be consistent with it. Don't use "break" one day and "okay" the next.
Here's another tip: when you have your dog in a sit or a down and you want to give your dog their release word, draw yourself away from the dog when you give the release word. This will help your dog figure out that they're released from the sit.
As always, good luck and reach out if you need help!