ok , so i've seen the video, twice now.
and yet , im not getting it.
how its possible to confirm a block if no transaction was made ?
Note that the video is talking in general terms about how a system like bitcoins works, so rather than calling the value of the money in the system "Bitcoins", it calls it "Ledger Dollars". Anytime he mentions "Ledger Dollars" he's talking about what the Bitcoin system calls "Bitcoins".
Starting at 17 minutes and 50 seconds in the video...
(This link should start the video at that point)
https://www.youtube.com/watch?v=bBC-nXj3Ng4&t=17m50s
"To reward a block creator for all this work, when she puts together a block, we'll allow her to include a very special transaction at the top of it in which she gets, say, 10 ledger dollars out of thin air. This is called the block reward, and its an exception to our usual rules about whether or not to accept transactions. It doesn't come from anyone, so it doesn't have to be signed. It also means that the total number of ledger dollars in our economy increases with each new block. Creating blocks is often called mining, since it requires doing a lot of work, and it introduces new bits of currency into the economy. But, when you hear or read about miners, keep in mind that what they're really doing is listening for transactions, creating blocks, broadcasting those blocks, and getting rewarded with new money."
So the "coin is being created" by the miner assigning value to themselves in the special "block reward" transaction. Then they include that transaction in the block that they create (along with any other transactions that they want to include, if any) and they begin the proof-of-work. Once the proof-of-work is completed, they broadcast the block to the network.
Therefore there is ALWAYS at least one transaction available for the miner to include in the block that they are working on (the block reward transaction).
Let say we just created the software, and we are going to work in the first block of the chain. We create a transaction that pays us 50 BTC. We then build a block with this transaction. Next we complete the proof-of-work on this block. Finally we broadcast this block to everybody that has our software.
Which part don't you understand?
