The blockchain will continue to grow forever, only the mining reward is decreasing.
Does this means that if no more Bitcoins are generated, the blocks are still created at the same speed (2016/10 min average) and the blockchain still running with the same number of transaction maximum possible / day?
Yes, assuming there aren't any technology (which can solve scaling problem) applied to Bitcoin.
Also does this means that Bitcoin can continue to work without miners, just using these blocks automatically generated every 10 min?
No, miners is still needed. Additionally, they still get reward from transaction fee from transaction which included on blocks they mine.
Blocks and Bitcoins are not the same thing I understand. Blocks can host transactions, or mining rewards, that are a special kind of transaction. The max number of transaction is constant, but the bitcoin creation is halved every 4 years.
Am I right?
Yes, block can host/store transaction. In fact, all transaction must stored/included in blocks.
Yes, block must have coinbase transaction, which is transaction about mining reward for the miner/pool.
No, maximum transaction amount on blocks depends on each transaction size.
Yes, bitcoin
creation mining reward is halved every 4 years.