jsonを読み込み、値をテンプレートに当て込みhtmlに挿入します

const fs = require('fs');
const { execSync } = require('child_process');
const ejs = require('ejs');

const template = fs.readFileSync('./template.html', 'utf-8');
const data = JSON.parse(fs.readFileSync('./data.json', 'utf-8'));
const html = ejs.render(template, data);

fs.writeFileSync('./index.html', html);
execSync('open index.html');