const tag = (strings, ...values) => {
  return strings.reduce((result, str, i) => {
    const val = values[i - 1];
    const transformed =
      typeof val === "number" ? `[${val ** 2}]` : `{${val?.toUpperCase()}}`;
    return result + transformed + str;
  });
};

const name = "nova";
const level = 3;
const score = 97;

const output = tag`Player: ${name} | Level: ${level} | Score: ${score}`;
console.log(output);