Proteus simulation problem (beginner) - "Power rails 'VCC/VDD' and 'GND' are interconnected in net GND" errors
The error messages from Proteus are correct. In your schematic, you have shorted Vcc to Gnd.

Here is the relevant part of the original, correct, schematic from your Instructables link - it has no short between Vcc and Gnd:





Notice how your schematic is different in that area which I marked:





The solution (as commented by G36) is to fix your schematic, including removing the short which you have between Vcc and Gnd.