Can I see the precise breakdown of the achievements' percentage obtained in Steam?
You can view precise percentages for each achievement at the URL below.
http://api.steampowered.com/ISteamUserStats/GetGlobalAchievementPercentagesForApp/v0002/?gameid=291650
Change the number at the end to the appid of the game. You can find that as the number in the URL of the store page for the game you're interested in. You can not view the number of people who achieved it out of a total number of players.