entering the working time, automatically marked with color in the timeline.

NikolinoDE 

No problem. Here is the code you need to place on Next month's Sheet module.

Public sTimeFound As Boolean
Public sColumn  As Long
Public eColumn  As Long

Private Sub Worksheet_Change(ByVal Target As Range)
If Target.CountLarge > 1 Then Exit Sub
Dim timeType As String
Dim dt As Date
Dim empRow As Long
Dim startCell As Range
Dim timeRng As Range
Dim dtCel     As Range
Dim tCel    As Range
Dim dtRng   As Range
Dim emp     As String
Dim n       As Variant
Dim dws As Worksheet
Dim empRng  As Range
Dim inputRng    As Range
Dim clr         As Long

Set dws = Worksheets("IND1")
Set empRng = dws.Range("H1:Q1")


Set dtRng = dws.Range("C8:C348")


Set timeRng = dws.Range("F8:BA8")

Set inputRng = Range("I10:EZ40")

Application.EnableEvents = False
If Not Intersect(Target, inputRng) Is Nothing Then

    timeType = VBA.Trim(Cells(9, Target.Column).Value)
    emp = Cells(5, Target.Column).MergeArea.Cells(1).Value
    n = Application.Match(emp, empRng, 0)
    clr = empRng.Cells(n).Interior.Color
    
    If IsError(n) Then
        MsgBox "The employee " & emp & " doesn't exist on " & dws.Name & " Sheet.", vbExclamation
        GoTo Skip
    End If
    
    If (LCase(timeType) = "from" Or LCase(timeType) = "to") And Target <> "" Then
        dt = Cells(Target.Row, 2).Value
        For Each dtCel In dtRng
            If dtCel.Value = dt Then
                empRow = dtCel.Row
                empRow = empRow + n
                Exit For
            End If
        Next dtCel
        For Each tCel In timeRng
            If CDate(tCel.Value) = CDate(Target.Value) And LCase(timeType) = "from" Then
                sColumn = tCel.Column
                With dws.Cells(empRow, sColumn)
                    .Value = Target.Value
                    .NumberFormat = "hh:mm"
                End With
                sTimeFound = True
                Exit For
                
            ElseIf CDate(tCel.Value) = CDate(Target.Value) And LCase(timeType) = "to" Then
                eColumn = tCel.Column
                With dws.Cells(empRow, eColumn)
                    .Value = Target.Value
                    .NumberFormat = "hh:mm"
                End With
            End If
        Next tCel
        
    End If
    If sColumn <> 0 And eColumn <> 0 And sTimeFound = True Then
        If Application.Count(dws.Range("F" & empRow, dws.Cells(empRow, sColumn - 1))) = 0 Then
            dws.Range("F" & empRow, dws.Cells(empRow, sColumn - 1)).Interior.ColorIndex = xlNone
        ElseIf Application.Count(dws.Range(dws.Cells(empRow, eColumn + 1), "BA" & empRow)) = 0 Then
            dws.Range(dws.Cells(empRow, eColumn + 1), "BA" & empRow).Interior.ColorIndex = xlNone
        
        End If
        dws.Range(dws.Cells(empRow, sColumn), dws.Cells(empRow, eColumn)).Interior.Color = clr
        
        sColumn = 0
        eColumn = 0
        sTimeFound = False
    End If
End If
Skip:
Application.EnableEvents = True
End Sub


Private Sub Worksheet_SelectionChange(ByVal Target As Range)
    
    Unprotect "1234"
    
    With Range("A10:EZ40").Interior
        .Pattern = xlSolid
        .PatternColorIndex = xlAutomatic
        .PatternTintAndShade = 1
    End With
    
    If Not Intersect(Target, Range("A10:EZ40")) Is Nothing Then
        
        With Range(Cells(Target.Row, 1), Cells(Target.Row, 156)).Interior
            .Pattern = xlGray25
            .PatternThemeColor = xlThemeColorAccent2
            .PatternTintAndShade = 0.399945066682943
        End With
        
        Application.EnableEvents = False
        Target.Activate
        Application.EnableEvents = True
        
    End If
    
    Protect "1234"
    
End Sub

Also, don't forget to mark the post with the proposed solution as a Best Response. 🙂

Thanks for all your wishes.

Have a good time ahead!