Block diagram itself is pretty much self explanatory. Drafting schema is not a tough job but, You need to simultaneously take care of the part that you are selecting for - footprint, availability and Pricing.
Undoubtedly, EAGLE is superior CAD tool, no matter How small or Big is your project. I have been using EAGLE for past 2 Years, And I still discover NEW things everyday.
MCU +3V3 Powerd | 8MHz Clocked:
28-PinDIP, for easy Plug-Play and Programming, In case You end-up burning one.
LM1117 LDO for +3V3 Regulation and DC Power Jack which allows you to power the board over 9V/12V Power adapter.
As stated in details related board, Inspired from Real Bare Bones.
Simple and Easy USB-to-TTL interface for Burning sketches, Serial debugging.
+3V3 Powered Low Cost ESP-01 module. Easily available in electronics market or Online ebay/Amazon etc.
Widely used in industry for Cold Junction compensation and other applications. Output in 10mV/DegC.
Light Dependent resistor, See how easy it is to interface. On the next second you can start playing with it, building cool applications.