How do I send coins from the game to my wallet?
Oh thank you for playing the game. I promise to implement the withdraw function in the next 24 hours. I didn't do that because no one required lol. Sorry for inconvenience.
These things happen, though usually such things are picked up in the initial design stages of a game from my own experience.
As to what a blockchain explorer is, what better example than this one for Bitcoin:
https://blockchain.info/Oh surely it is, but you know I am busy these days... Sorry.