Unable to program ATtiny84A with Arduino Nano as ISP – “Invalid device signature”

On the Nano you are using as an ISP programmer, after you upload the ISP sketch install the 10uF capacitor from GND to Reset. Neg lead on GND. That prevents the serial session you open with avrdude from resetting the Nano. You don’t need any other electrolytic capacitors.

I suggest you get accustomed to drawing schematics, they will help us help you. A hand drawn schematic is fine.