How do Chinese typewriters work?

Are there thousands of keys for every letter?
Or are there “merely” few hundred most frequently used?

You have to understand how Chinese characters are written. There are no letters, but there are components and these components are written in a commonly set order. Nowadays, with the software that’s available, someone can start typing a character by starting with the first component, the software will start “filling in” the other parts. The software can even anticipate the next character based on what has already been typed. This is a vast improvement over the old days, but it’s still a lot more cumbersome than typing in English.

The answer to your OP question:

WAG Exactly like any other typewriter. Hit a key, print a character. :rolleyes:

OH. What you meant to ask was:
“What characters are used by a Chinese typewriter?”
Probably PC’s with whatever character set they can get.

But what was used before the PC era?

Were western mechanical typewriters used to type Pinyin or similar?

A somewhat-relevant article by the Perfect Master.

I’ve never understood why Cecil ended the article with “Japanese, now . . . they say Japanese is really complicated”, since the Japanese system for text entry is pretty much the same as for Chinese, but simpler.

More on topic with the OP’s question is a quote From a book I’m reading at the moment, Language Planning and Language Policy: East Asian Perspectives:

If that’s the case for Japan, it must have been even more true for China. Which isn’t to say that they didn’t try. Here is a picture of a Chinese typewriter from the 70’s. Another can be found here.