Nowadays I am seeing that many people are complaining about the slow confirmation and they often get the answer as the number of transactions nowadays is high. So I think if the number of miners increase then will it solve the problem?
no
At this moment, the protocol is designed so on average 1 block with a maximum size of 1 Mb will be found with a hash below target every 10 minutes.
I am thinking that suppose there will be one miner in confirming two transactions and on other hand there will be two miners to confirm two transactions of the same size as below then will not it be faster according to that sense?
I updated my first post while you were replying... i added some more text that should answer this question.
Let's scale it down a bit, and look at this (imaginary) example:
The bitcoin network only has 1 miner... The miner has one ASIC that runs at 1 Th/s 24/7. There always was only 1 miner, the time between blocks is ~10 minutes.
Since there is a huge backlog, all blocks are always filled, so there are ~144 blocks =~ 144 Mb of transaction data per day
One day, a second miner joins the network, he also has 1 Asic hashing at 1 Th/s.
The first couple of days, the total hashrate has doubled, so on average, twice as much blocks get added to the blockchain (since both miners still use the original difficulty, so on average, they'll each be able to produce ~144 blocks/day with a hash that is lower than the current difficulty). However, after a couple of days, the network does a difficulty adjustment, the diff goes up, so the chance each miner finds a hash that is lower than the current (new) diff goes down to 50%.
After the diff adjustment, the first miner no longer finds ~144 blocks/day, he now finds ~72 blocks/day, as does the second miner.
The maximum number of blocks that could potentially be mined at "double speed" is 2016, since the network readjusts it's diff every 2016 blocks.
