Add it in your settings.gradle.kts at the end of repositories:

dependencyResolutionManagement {
	repositoriesMode.set(RepositoriesMode.FAIL_ON_PROJECT_REPOS)
	repositories {
		mavenCentral()
		maven { url = uri("https://jitpack.io") } 
	}
}

Step 2. Add the dependency

dependencies {
        implementation("com.github.2mori:ByteSerializer:main")
}