Using the function ShowAnyForm of Cpearson this can be done with a class module.
An example with the following VBA project tree:

Form
An example with the following Form:

A form with two buttons with the name of the form that should be opened.
And with the following code:
Private collBtns As Collection
Private Sub UserForm_Initialize()
'Créditos: www.andypope.info
' www.cpearson.com/excel/Events.aspx
Dim cls_btn As Classe1
Set collBtns = New Collection
For Each ctrl In Me.Controls
If TypeName(ctrl) = "CommandButton" Then
Set cls_btn = New Classe1
Set cls_btn.btn = ctrl
collBtns.Add cls_btn, CStr(collBtns.Count + 1)
End If
Next ctrl
End Sub
Class module
This code is inserted in the class module Classe1
Public WithEvents btn As MSForms.CommandButton
Private Sub btn_Click()
ShowAnyForm (btn.Name)
End Sub
Private Sub ShowAnyForm(FormName As String, Optional Modal As FormShowConstants = vbModal)
'http://www.cpearson.com/Excel/showanyform.htm
Dim Obj As Object
For Each Obj In VBA.UserForms
If StrComp(Obj.Name, FormName, vbTextCompare) = 0 Then
Obj.Show Modal
Exit Sub
End If
Next Obj
With VBA.UserForms
On Error Resume Next
Err.Clear
Set Obj = .Add(FormName)
If Err.Number <> 0 Then
MsgBox "Err: " & CStr(Err.Number) & " " & Err.Description
Exit Sub
End If
Obj.Show Modal
End With
End Sub
In this, the button clicks event is declared in btn_Click().
That with the click of the button, will open the form of the same name of the Button with the function ShowAnyForm.
The options you can use to display the form are vbModal and vbModeless
Example:
Private Sub btn_Click()
ShowAnyForm btn.Name, vbModal
End Sub
Private Sub btn_Click()
ShowAnyForm btn.Name, vbModeless
End Sub
Upshot

I adapted in my design and it worked perfectly. Thank you very much
– user123166
Dear friend, how do I paste in the active userForm texbox1 the value of sheet A1? "Userformativo". textbox1.value = Sheets("plan1"). range("a1"). How do I declare the statement to mean "Active Userform"?
– user123166