Since your holidays are listed chronologically throughout the year in columns A:B, you should be able to just use this.
If January 1 was not in a holiday period you would need a slight adjustment but I'm guessing that in your location January 1 will always be a holiday.
Excel 365 (Windows) 32 bit
<colgroup><col style="width: 25pxpx"><col><col><col><col><col></colgroup><thead>
</thead><tbody>
[TD="align: center"]1[/TD]
[TD="align: right"]Start[/TD]
[TD="align: right"]End[/TD]
[TD="align: right"][/TD]
[TD="align: right"]Date[/TD]
[TD="align: right"]In Holiday?[/TD]
[TD="align: center"]2[/TD]
[TD="align: right"]1/01/2020[/TD]
[TD="align: right"]5/01/2020[/TD]
[TD="align: right"][/TD]
[TD="align: right"]3/01/2020[/TD]
[TD="align: right"]TRUE[/TD]
[TD="align: center"]3[/TD]
[TD="align: right"]15/02/2020[/TD]
[TD="align: right"]23/02/2020[/TD]
[TD="align: right"][/TD]
[TD="align: right"]21/01/2020[/TD]
[TD="align: right"]FALSE[/TD]
[TD="align: center"]4[/TD]
[TD="align: right"]4/04/2020[/TD]
[TD="align: right"]19/04/2020[/TD]
[TD="align: right"][/TD]
[TD="align: right"]1/11/2020[/TD]
[TD="align: right"]TRUE[/TD]
[TD="align: center"]5[/TD]
[TD="align: right"]23/05/2020[/TD]
[TD="align: right"]31/05/2020[/TD]
[TD="align: right"][/TD]
[TD="align: right"][/TD]
[TD="align: right"][/TD]
[TD="align: center"]6[/TD]
[TD="align: right"]21/07/2020[/TD]
[TD="align: right"]30/08/2020[/TD]
[TD="align: right"][/TD]
[TD="align: right"][/TD]
[TD="align: right"][/TD]
[TD="align: center"]7[/TD]
[TD="align: right"]24/10/2020[/TD]
[TD="align: right"]1/11/2020[/TD]
[TD="align: right"][/TD]
[TD="align: right"][/TD]
[TD="align: right"][/TD]
[TD="align: center"]8[/TD]
[TD="align: right"]19/12/2020[/TD]
[TD="align: right"]31/12/2020[/TD]
[TD="align: right"][/TD]
[TD="align: right"][/TD]
[TD="align: right"][/TD]
</tbody>
Check Holidays
[TABLE="width: 85%"]
<tbody>[TR]
[TD]
Worksheet Formulas[TABLE="width: 100%"]
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[TH="width: 10px"]Cell[/TH]
[TH="align: left"]Formula[/TH]
[/TR]
</thead><tbody>[TR]
[TH="width: 10px, bgcolor: [URL=https://www.mrexcel.com/forum/usertag.php?do=list&action=hash&hash=F0E0E0]#F0E0E0[/URL] "]E2[/TH]
[TD="align: left"]=VLOOKUP([COLOR=rgb(255]D2,A$2:B$8,2[/COLOR])>=D2[/TD]
[/TR]
</tbody>[/TABLE]
[/TD]
[/TR]
</tbody>[/TABLE]