ok, so apparently I have this game. How much do you have to play to get to level 20 before 18th?
It's curiously difficult to find information on how much XP is required per level up in this game. The best I could do is
this forum post that tallies it up to level 10. If we reasonably assume that each level from 10 to 20 will need at least 4.75 million XP, the total requirement is north of 50 million XP.
From my anecdotal experience, you get between 50-100k XP per game depending on it's length. It usually comes in at 70-80k. There's a 50k bonus if you win the game as well. Assuming you win half your games, it roughly adds up to 100k per match.
If you play solo, you'd need to get 50 million XP @ 100k per match so that's over 500 games.
If you play with a friend, you get a 50% XP bonus which give you 150k XP per game meaning you'd play over 300 games.
Best case scenario: if you win every one of your games and you play them all with a friend, you'll get about 200k XP per game so you'd
only need to win 250 matches.
Daily quests give you up to 100k XP per day so if you did those every day until the 18th you'd reduce the requirement by another 1.5 million XP or so.
Unless I'm missing some source of XP or my mathematics is horribly wrong, you're looking at hundreds of games played to reach level 20.