Hi Ac,
To get to the Self Clean feature, tap the three-line menu icon on the control panel, select "Cleaning", then choose "Self Clean". From there, you can pick your preferred cleaning time and start the cycle.
For additional guidance, you can refer to pages 51–53 of the user manual, where you'll find detailed steps for using the self-cleaning function:
https://downloadcenter.samsung.com/content/UM/202311/20231122161711134/01._FULL_NE63T8911SS_NE63T8911S-04_EN.pdf
Hope this helps!
Jeffrey
Samsung Care