Articles including "the" are necessary in English, not only because they are integral to the syntax and grammar that form the structure of the language, but also because they convey some important elements of meaning that are currently communicated briefly and efficiently through the use of articles.
I am Indian just like you, and I can see where your question comes from. We Indians are used to understanding English without giving much importance to articles, not least because many Indians (not you and I) don't use them properly, and we learned to do without.
[Members please note: this Q is therefore not trivial or a duplicate but an outcome of how non-native speakers perceive the structure of the English language relative to its applied function.]
For many non-native English speakers like Chinese and Indians, the only function of the English language is often to convey some sort of literal meaning in communication:
I not going school today.
Father asked me go to bank and pay bill.
This is rudimentary English spoken/written without basic expertise, but we can infer the correct meaning most of the time, even if someone did not include the article a/ an/ the. However, articles serve some important functions to convey precise meanings that don't need to be guessed at:
Definite Article: the
The definite article is used before singular and plural nouns when the noun is specific or particular. "The" signals that the noun is definite, that it refers to a particular member of a group. For example:
"The dog that bit me ran away." Here, we're talking about a specific dog, the dog that bit me (...)
"I saw the elephant at the zoo." Here, we're talking about a specific noun. Probably there is only one elephant at the zoo.
Grammaticality is often the main consideration. To write the same sentences as "dog that bit me ran away" and "I saw elephant at zoo" would be considered ungrammatical and a sign of underdeveloped English skills, even if a competent English user did it thinking the article superfluous. That's because articles are part and parcel of the language, and expected in both speech and writing.
However, the definite article does convey special and important meaning when it picks a particular noun out of a group of similar nouns, or creates a sense of "the most fitting"/ "the absolute" which meaning would be lost by omitting "the": as in
Spain is the team to beat at this World Cup (the best of all teams)
Mahatmaji was the personification of human virtues (the absolute exemplar, among all people)
Kim is the man for the job (just the right man for the job!)
Maybe the meaning is clear in most cases without the use of "the." That doesn't mean that articles including "the" can be omitted without disrupting the formal structure of a language that has articles. Even the informal spoken form is influenced by this structure. This is the form the language has evolved into over centuries.
All languages including French, Spanish, Hindi and Tamil have such words that look unnecessary from outside but are integral to the syntax and grammar when looked at "from inside." Articles like "the" are essential in English -- not necessarily to convey meaning (although the meaning they convey is often significant), but for being grammatical, and to preserve the structural integrity of the language. Rather more importantly it defines the language. To make this point more effectively I quote here Dan Bron's comment under the question:
It’s not that it’s impossible not to have them, of course, it’s that they’re “not useless” but more importantly “not English” without them. You’d be talking about some other language. Sure, we can imagine English without articles. And also without written vowels. And also without affixes, or as agglutinative, or whatever, but then you’re talking about another language, which will make it easier to talk about some things and harder to talk about others. It’s the Sorties paradox. Articles convey meaning and provide function in English, and no, you can’t have English without them.