The most popular was probably Courier, but some were sold with Quadratto, and probably others.
Pica and elite.
Just about anyone, with a little practice can learn to use a typewriter. Of course you need to be able to speak the language the typeface is set in and of course be able to spell.
Words beginning with 'type' are: type typewriter typecast typeface typeset typesetter typestyle
Words beginning with 'typ' are: type typewriter typecast typeface typescript typeset typesetter typestyle typography typist typographical error typhoid typhoon typhus typical typify
Typeface is the design of a set of characters, such as Courier, Helvetica and Times Roman. Typeface and font are used interchangeably; however, the typeface is the primary design and the font is the implementation and variation of the typeface, such as bold, italics, etc.
Impact - typeface - was created in 1965.
Papyrus - typeface - was created in 1983.
Hobo - typeface - was created in 1910.
Courier - typeface - was created in 1955.
Fairfield - typeface - was created in 1940.
Albertus - typeface - was created in 1932.
Eagle - typeface - was created in 1934.