We know that a block size is 1M,and produced about 10 minutes.
There is nothing like "block size" anymore in bitcoin since Segwit got activated, instead there is the
concept of block weightThere is a block weight of 4MB.
So blocks can be
larger than 1MB in size1 block consists of 2 thousands transactions.
A block can have way more --or less -- than 2,000 transactions depending on the block weight of the individual transactions.
My question what if more than 2 thousands transactions done globally within 10 minutes? How bitcoin system handle this?
They transactions that don't fit in a block wait in the "mempool" until they are added to a block by a miner.
Because of the scarce block space, miners are incentivized to pick high-fee transactions over low-fee ones, so the transactions that pay higher fees usually get added to a block while the ones with lower fees wait in (the) mempool until they are added.
The mempool of a node can grow large (past 180MB at times) and if it gets filled up, transactions with low fees are dropped and have to be broadcast again.