I am currently designing a circuit for a custom pcb with an ESP-12F and USB-C.
As I could not find any circuits using USB-C and I am not that experienced in elctronics I am not sure if with this circuit I will be able to power and flash the ESP-12F and a few leds and it would be great if someone could confirm if this circuit will work.
I share @Idahowalker's concern that you are using a resistor voltage divider as a power supply.
You are also missing some important pullup and pulldown resistors, a reset switch and a way to put the chip into programming mode. Certain pins must be a defined levels for the boot sequence to work right.
I have now adjusted my circuit according to your diagramm and also added the voltage regulator from your resource. In the resource you mentioned, it was also stated that my usb to serial needs to run on 3.3V as well or else I might fry the ESP, but why would that matter? The power pins of the chips aren't connected, only the data pins.
May I suggest that a polarized cap be placed at the 3.3V regulator output as well? The current demands of the ESP's when getting ready to transmit is served well with a polarized cap. I typically put a 47uf Tantalum and a 10nF ceramic on the output of the 3.3V with ESP32's ( I know its not an ESP32).
I found that by using a separate 5V power regulator for the light strip, ground tied together cured many headaches I was having with random noise flashing the LES's.