how to check the checkbox in vue code example

Example 1: vue checkbox

<input type="checkbox" id="checkbox" v-model="checked">
<label for="checkbox">{{ checked }}</label>

Example 2: vuejs checkbox

<input type="checkbox" id="jack" value="Jack" v-model="checkedNames">
<label for="jack">Jack</label>
<input type="checkbox" id="john" value="John" v-model="checkedNames">
<label for="john">John</label>
<input type="checkbox" id="mike" value="Mike" v-model="checkedNames">
<label for="mike">Mike</label>
<br>
<span>Noms cochés : {{ checkedNames }}</span>