Voting system in Microsoft Access

Good morning, I just need you to help me with a code.

I need to make a voting system, I already have the table ready but my code does not do what I asked.

There are two questions:

A) How do I correctly validate that the user has checked a checkbox? B) How do I add a vote to the voter in question?

This is what I have so far:

-Code:

 Private Sub Comando25_Click()
 Check1 As Boolean
 Check2 As Boolean
 Check3 As Boolean
 Check4 As Boolean

 If Me.Check1 = True & Me.Check2 = True & Me.Check3 = True & Me.Check4 = True 
 Then
 MsgBox "No puedes seleccionar los cuatro, solo puedes seleccionar uno"
 DoCmd.Close
 DoCmd.OpenForm "Ir a"
 End If

 If Me.Check1 = True & Me.Check2 = True & Me.Check3 = True Then
 MsgBox "No puedes seleccionar tres, solo puedes seleccionar uno"
 DoCmd.Close
 DoCmd.OpenForm "Ir a"
 End If

 If Me.Check1 = True & Me.Check2 = True Then
 MsgBox "No puedes seleccionar dos, solo puedes seleccionar uno"
 DoCmd.Close
 DoCmd.OpenForm "Ir a"
 End If

 If Me.Check2 = True & Me.Check3 = True Then
 MsgBox "No puedes seleccionar dos, solo puedes seleccionar uno"
 DoCmd.Close
 DoCmd.OpenForm "Ir a"
 End If

  If Me.Check1 = True & Me.Check3 = True Then
MsgBox "No puedes seleccionar dos, solo puedes seleccionar uno"
DoCmd.Close
DoCmd.OpenForm "Ir a"
End If
End Sub

This is what the form looks like:

This is how the table looks: (Votes is a variable number, of course)

I await your response