How to connect power to multiple pins on a microcontroller?
I'm assuming you are using the LQFP32 package and a 2-layer stackup, is that correct?

What do you mean by "polygon" on bottom layer? Are you referring to ground pour?

Is you part placement final? (I'm taking the liberty to assume "no").

Using screenshots of your layout, here what I would suggest:


flip LDO circuit to top layer (there is still a lot of space)
re-arrange circuit so that LDO's VCC output and caps are close to MCU pin 17
feed pin 1 and 5 using thick trace underneath MCU (or even a shape)
use thicker traces (= pad width) to connect to decoupling capacitors


Doing so your bottom layer is completely free for ground pours or routing traces, the board is one-sided (all components on top side) and you don't need to switch layers to feed power into the MCU.