How did they program keyboard?

By implementing the keyboardinput in hardware.

i fear for the future of our field

Using a virtual keyboard, obviously. Don't be dumb.

With the mouse and the character map in windows, duh?

They didn't.

Keyboards still at their core consist of a pretty stupid matrix of switches electrically arranged in a matrix and a digital circuit scanning the matrix for shorts between rows and columns detecting the key presses.
Back then, they where either interfaced via a primitive parallel or serial interface - the latter was pretty universal but they never called it that...

They probably turned on the on screen keyboard.

Which came first? The chicken or the egg?

If we talk about keyboard, first programs used physical configurations, triggers, wires… meanwhile keyboard had a career in typewriter industry.

Then someone thought took a few ideas and mixed them.

@rov3rand0m the egg comes first

@darksideofyay but where did it come from

@electrineer from an animal that wasn't a chicken. ✨ evolution ✨

This question must go deeper than we initially assumed...

@Oktokolo

The reason Linux refers to the terminals with the name TTY (TeleTYpe), is because the first Unix terminal devices were repurposed telegram machines, which used a mechanical typewriter for input and paper for output.

Bootstrapping. No, not that thing to build websites.