The right way to control EN pin of TPS63806 using STM32 MCU
Neither makes sense.
Directly connect your MCU output to the enable pin.
Your MCU produces ca 0V in LOW output state and ca 3.3 V in HIGH output state.
The datasheet of your TPS clearly says the on/off threshold voltage is somewhere around 1 to 1.1 V. So, with your GPIO low you're solidly below that, and with its high solidly above it. All good!
So, nothing needed. Your voltage divider would only make sense if you needed a lower voltage, your MOSFET only if.. no, it simply doesn't make sense, and both ideas also seem to be designed to do the exact opposite of each other!
Also, I do hope your lithium cell has battery protection built in! You don't want to deep-discharge it (which you can definitely do this way), as that will render the battery useless, and you definitely don't want to accidentially short-circuit it (as that also renders the battery useless, but potentially also makes it an explosive device).