What means お before person's name and how to read kanji after お?


I'm reading Kidou Okamoto's Japanese novel right now. It was written in 1950
and its title is "半七捕物帳 01 お文の魂". I noticed that in this novel there are lots
of female names that starts with お.

Here are examples: お文 お道 お春

What means お before names? Is it still common in Japan to give names that
starts with お? Was it used only for female names or for male names too? How to
read kanji after お - in 音読み or 訓読み?

Thank you in advance! It's really important for me because I'm trying to
translate this novel to my native language.

Here is novel's link:
<https://www.aozora.gr.jp/cards/000082/files/1005_14977.html>

