How bitcoin handle users limit if only 4000 transactions in every 10 minutes ? Let's say I transfer 2 bitcoin to Anuj account then how much time maximum it will take to reflect in Anuj's account and what will be the process running in background on bitcoin during this record.
Let's say I transfer 2 bitcoin to Anuj account
The Bitcoin network doesn't have accounts as such. You typically transfer money to a Bitcoin "address" given to you by the intended recipient.
how much time maximum it will take to reflect in Anuj's account
It depends on how busy the Bitcoin network is and on the transaction fee chosen by the sender. I don't think there is an imposed maximum but if the sender selects a very low fee and the network is busy, it can take many days.
what will be the process running in background on bitcoin during this record.
No process needs to be running in the background.
You can receive money when your computer is turned off. Receiving money typically doesn't require any participation from the recipient after the sender knows the receiving address.
Obviously, a Bitcoin wallet can only find out it has previously received money by catching up when next online.
Time interval between two blocks can be less than 10 minutes or more than 10 minutes
On an average it stays close to 10 minutes with the help of difficulty adjustment
One block may have only one transaction or thousands of transactions
Most of the blocks after segwit have size greater than 1 MB
Your transaction has some inputs and outputs which mainly decides the size of a transaction
You as a user decide the fee rate for the transaction in sat/vbyte. So you are bidding for the block space in satoshis to get your transaction included in the block.
Miners prioritize transactions based on fee rate and higher fee rate transactions get confirmed quickly
Visual representation of how mempool looks for a full node : https://mempool.observer
Mempool is a pool in which transactions remain until included in a block by some miner, mempool for a full node can be different from another full node