india china has roughly the same population but china had thrice more land/resources plus china had a big advantage of developed neighbours like korea and japan.
https://en.wikipedia.org/wiki/Land_use_statistics_by_country
India actually has more arable land than China. Most of China's area is mountain and desert, that includes large portions of Southern China (mountains). This boosts the importance of infrastructure and make development relatively difficult and capital heavy compared to a flatter nation. Per unit of area, China has greater agricultural production. Chinese farmers are simply more motivated for production due to the incentive/social structure and the efforts in agricultural technology. Every rural peasant family owns land and agriculture is deeply embedded in Chinese culture. At early stages this resolved subsistence but created large numbers of subsistence farmers. Later with greater capital inputs like tractors and other farm machines/technologies, greater production density could be achieved. These methods generally work in larger scale. Instead of selling their land, many farmers are creating collectives or companies with other farmers and hiring professionals for operations. The farmers lease the land to the company and get profit sharing, if they are in need of work they can work for the agro company. In other cases they can look for work in cities, start their own businesses, etc since they have a stable passive income.
Before China's opening up in 1979 there were efforts to increase the agricultural productivity in order to offset the rural productive labour displacement from urbanisation and factory production. These were successful and resulted in quite affordable and abundant food supply for the nation.
india, pakistan bangladesh and srilanka are continuously embroiled in a state of war and tension
State of war and tension is classic balance of power strategy, it can be put in place by an external force or self induced. Its cause is not that important, what is important is getting out of it and it is up to one's own nation to initiate such efforts, it is always easy to blame the situation. China amended it with Japan and other neighbours, apparent by the low military spending, China spends 1.3% of gdp and Japan spends 1% of gdp on military. Yes, there is tension and disagreements but that is quite normal, both nations cooperate economically quite well.
china was never colonised so its resources were not looted through colonialism compared to 200 years of british colonization in india.
Although there was no colonization, China paid a heavy price for the opium wars and first sino-japanese war. A great sum of money was paid out and China paid the equivalent of 6.4 times Japan's government revenue for the first sino-japanese war.
secondly india is very multiethnic and there seem to lots of conflicts, china is one ethnicity mainly han chinese so it makes things easy
Ethnic groups are the product of common history and certain cultural traits/beliefs. Ethnic groups can be destroyed and new ones can be created but their descendents can genetically live on as new ethnic groups. That has been the reality throughout history and will be true in the future.
india doesnt have the same dynamic as china, china is a commie state, everything is implemented on push of a button, where as india needs to deal a lot with bureaucracy, plus has to take along with all sorts of opinions and conflicts which is not possible with a push of a button.
As long as people are stuck in the war of "low level ideologies" they will be chained to a functionally external narrative for internal development. AKA communism vs capitalism, autocracy vs democracy, religion A vs religion B, the list goes on. Most outsiders don't understand how China works simply because they don't understand Chinese language and culture.
What is the purpose of bureaucracy but to facilitate a desired outcome?
in one millennium you were ruled by foreigners for 700 years by mongols and manchus, only original chinese government was ming dynasty.
your communist regime was formed in 1949 where as indian democratic regime was founded in 1947, so infact indian governance is older than yours.
unlike china india cannot be governed by communist regime, and even in a less multicultural country like pakistan, dictatorial regime was never accepted, it came and then it went away.
indian democracy is actually performing miracles how it is not only governing country like india but also making a lot of progress in past few decades.
not to mention inda was looted and plundered by british for 200 years, india was a lot poorer than china when it ained its independence so its not expected that india will miraculously overtake china especially when china has far more resourses being three times the size of india with equal population.
While the PRC was founded in 1949, China is a continuous civilisation for 5000 years, its governing structure has long roots irrespective of its name, a reason why you can't understand contemporary China through "isms". China is a bigger concept than any ethnic group, its civilisation lives on. Its not a classic nation state. Saying China doesn't exist because its leader was mongolian or manchu is like saying Europe as a concept doesn't exist because Germans became Europe's leader instead of Romans or that London is not British since it has a Muslim mayor of Pakistani heritage. Today Germans use Latin script, today Manchus use Han script. Han ethnic group itself was the product of hundreds of tribes or old ethnic groups. Are Americans not American because they don't have ancestors from the mayflower?
"Miracles" like what? can you specify? I want to learn more.
Most of China's population is in the Eastern lowlands due to rainfall and geography.