Hello [email protected],
On the S32K11x derivatives, there are single ISER, ICER, ISPR, ICPR registers and eight IPR registers.
To enable the PORTA interrupt, you need to set the 9th bit of the ISER register.
S32_NVIC->ISER[0] |= (1 << 9);

Then, you can set its priority in the IRQ1 bit-field of the IPR2 register.
S32_NVIC->IPR[2] |= S32_NVIC_IPR_PRI_1(0b01000000);
As you can see below, there are only four priority levels.

If the interrupt does not work in RUN, please share a test project.
Thank you,
BR, Daniel