Here's a basic example that shows the radio buttons working

<EditForm Model="radioModel" OnValidSubmit="HandleValidSubmit">
    <InputRadioGroup Name="radioGroup" @bind-Value="radioModel.RadioValue">
        <InputRadio Value="0" />First Radio<br />
        <InputRadio Value="1" />Second Radio<br />
    </InputRadioGroup>
    <button>Submit</button>
</EditForm>

<span>Selected Value:</span> @selectedVal

@code {
    RadioModel radioModel = new RadioModel();
    int selectedVal;

    void HandleValidSubmit()
    {
        selectedVal = radioModel.RadioValue;
    }

    public class RadioModel
    {
        public int RadioValue { get; set; }
    }
}