Diana de Cabarrus

I'm a self-employed musician and my self employment includes performance and private teaching. I also strarted a part-time role in a school where I'm classified as a worker in October 2023. I have two queries - it looks like I'll need to complete self employment tax return and also the employment page - is that correct? And I had assumed I would not need to pay tax on my income from the part-time role because it is taxed at source. However, when I logged into the Gov.uk dashboard, that shows no tax or NI deductions even though I have a note from the school saying those are deducted. So do I enter that in the employment page as income even though it has already been taxed? Many thanks in advance.