Hello @IFrid.1 and welcome to the STM32 Community :smiling_face_with_smiling_eyes:,
1) Yes, STM32H753AI support SFI.
2) SWD can be used for SFI (SFI over JTAG is supported on STM32H7 series)
3) Let me check back with the expert team and I will come back to you with details.
I recommend you to refer to the AN4992 "Application note STM32 MCUs secure firmware install (SFI) overview", which provide an overview of the STM32 SFI solution with its associated tools ecosystem.
Hope my answer helps you.
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Imen