Here's all I could find

On Xbox consoles, see your time played:

Press the Xbox button  to open the guide, then select Game activity > All achievements. Select a game, then select Stats.

On the web, see your time played:

Sign in at account.xbox.com. Select your gamerpic (top-right), then select Xbox Profile > Achievements. Select a game, then select Achievements again. You’ll see your minutes played among the stats shown.

For a total ~~there might be some site or service that helps with that but I don't know of it.~~

Edit: actually Xbox is doing a year in review right now that has the total.