What is it mean for "Two block" mined?
This means it is the average time it needs for a new block to be mined.
For example: If a block has been mined right now, you can expect the next block to be mined in 10 minutes (on average) -> Time between 2 blocks being mined.
Let's say bitcoin has a block time of 10minute, so what is the confirmation?
The transaction gets the first confirmation when it will be included into the block.
This could be the next, the after next, or the 40th block from now on.
Once it is included into a block. Each block which builds upon, adds 1 confirmation to the transaction.
For example:
Currently are 80 blocks mined. You broadcast the transaction. It takes roughly 3 hours for it to confirm. Your transaction is being included into block #101.
It now has 1 confirmation.
Then, 60 minutes later, 6 new blocks have been generated -> we are at block #107 now. -> Your transaction has 6 more confirmations -> 7 confirmations in total.
On average(!) you get a new confirmation each 10 minutes (after the first one) because the average block time is 10 minutes.