https://www.behindthename.com/name/richard
...The change in the initial consonant is said to have been caused by the way the trilled Norman R was pronounced by the English.
And
-ch- is sometimes pronounced like a K (
Zachary,
Michael, Bach,
Chris, etc.).
“Dear optimist, pessimist, and realist – while you guys were busy arguing about the glass of wine, I drank it! Sincerely, the opportunist!”
-Lori Greiner