LP-MSPM0L1306: Code for timer interrupt from input interrupt

Use LP-MSPM0L1306.

Please tell me what kind of code I should write if I want to perform the following operation.

・First sleep state.

・When S1 (PA18) detects an input, an interrupt is generated, the sleep state is canceled, and the timer is started.

・500ms after the timer starts, a timer interrupt occurs and LED1 (PA0) outputs.