Regarding typing on Chol Moed, Halachapedia quotes
Rav Ovadia Yosef (Sh”t Yabia Omer 8:48(5)) writes that typing on a
computer is considered non-professional writing and would permit
typing up divrei torah one might forget or sending greetings for a
holiday need. Similarly, Igrot Moshe EH 4:73(4) implies that typing on
a computer isn’t considered a melacha.
Both seem to assume typing is a form of writing - just not a professional form of writing which would be assur on Chol Moed.
Moreover, in discussing texting on Shabbos, the OU writes:
Rabbi Shmuel Wosner (Shevet HaLevi 6:37), writing in 1983, ruled that
creating letters on a computer screen is Biblically prohibited. The
screen will not dissolve or rot and is therefore the equivalent of
parchment. The letters also will remain on the screen permanently,
unless someone actively erases them.
Although the OU brings many poskim who are lenient regarding not considering typing to be the equivalent of outright writing min haTorah, it seems typing would potentially be considered a form of writing - and thereby also require making Birchas HaTorah according to those who do so before writing.