• First, you are assigning item[index] to item[e.target.value] in if check , change = too ===
• Second, you have one state for both buttons, you have to keep 1 value for each button

if you just want to make that code work here is an working example:

const [sameText, setSameText] = useState([false, false]);

  const changeText = (e: any, index: number, item: any) => {
    if (item[e.target.value] === item[index]) {
      const newState = [...sameText];
      newState[index] = true;
      setSameText(newState);
    }
  };

and if check

<div>{sameText[index] ? 'C' : item[1][0]}<div/>

For N hotels you can use that:

const [clickedHotel, setClickedHotel] = useState(
    null,
  );

  const changeText = (e: any, index: number, item: any) => {
    if (item[e.target.value] === item[index]) {
      setClickedHotel(index);
    }
  };

and

<div>{clickedHotel === index ? 'C' : item[1][0]}</div>

You need to store the state for each button and change the state on click. Your buttons are rendered based on the button state

For example:

1. introduce const [buttonState, setButtonState] = useState(data);
2. map over buttonState instead of data
3. in changeText() change the state as you want by calling setButtonState()

You are using the nested arrays in the items array

You are almost there and you have done it correctly console.log(item[1][0]) will give you the

But there is one more thing you need to do is following:

import React, { useState } from 'react'

const App = () => {
  const data = [
    ['Hotel 1A', ['A']],
    ['Hotel 1B', ['B']],
  ]

  const [sameText, setSameText] = useState(false)

  const changeText = (e: any, index: number, item: any) => {
    console.log(item[1][0])

    // if ((item[e.target.value] = item[index])) {
    //   setSameText(true)
    // }
  }
  return (
    <div className='mx-auto'>
      <div className='flex p-16'>
        {data.map((item, index) => (
          <div className='mx-16' key={index}>
            <div className='p-12'>
              <button onClick={(e) => changeText(e, index, item)} value={index}>
                {item[0]}
              </button>
              <div>{sameText ? 'C' : item[1][0]}</div>
            </div>
          </div>
        ))}
      </div>
    </div>
  )
}

export default App