Assuming that electronic things refers to all electronic components (capacitors and resistors, inductors and semiconductors), They cease to work, leaving only mechanical devices or systems in operation.
How do you start? Transportation and its related systems (cars and buses, trucks, tractors and trains, planes, ships, elevators and traffic control systems, etc.) The system would cease to function. Communication systems (telephones, internet, satellites, television, radio, etc.) The system would cease to function. Infrastructure and related support systems (power generation and transmission systems, oil refineries/pipelines, air conditioning, sewage treatment, etc.) It would cease to be functional.
These and other cascading losses would cause the collapse of banking, commerce and industry as well as employment and civil society.
Imagine a world like the one in “The Walking Dead” except that there are no vehicles or zombies and people must survive by cooperating in small groups or using brutality until they can establish themselves as an agricultural society. This is necessary to feed 7.6 billion people. The world’s population would not have reached that level without electronic devices if it weren’t for infant mortality, disease, injury, and starvation.
The electro-magnetic mechanical relay is included in the electronic device list. This means that electronics were first used 283 years ago, when there was only 1 billion people on the planet and the average age of 37 years.