only one radio button checked at a time html code example
Example 1: html radio only one checked
<!--Just manke both names equal -->
<input type="radio" name="options" id="1"/>
<input type="radio" name="options" id="2"/>
Example 2: radio buttons
<input type="radio" id="male" name="gender" value="male">
<label for="male">Male</label><br>
<input type="radio" id="female" name="gender" value="female">
<label for="female">Female</label><br>
<input type="radio" id="other" name="gender" value="other">
<label for="other">Other</label>