I sent a coin to this address 3H6RQQthC5HV1BUYT38NpF9CJVgJzVkubp, I have a key from this address, but I do not know what to do with it and how to cancel the transfer
Where did you get the address from? A bitcoin or Litecoin wallet?
Is it your address?
You cannot cancel cryptocurrency transactions.
this was my btc wallet for which I sent a ltc! I can cancel using a key, but I do not know how