How do we connect input box value into a variable in JavaScript and html

Question

I want to store value of input box into a variable so that I can manipulate it.

Answer 1

https://www.w3schools.com/jsref/dom_obj_text.asp

Answer 2

Here:
https://code.sololearn.com/WAyKuCjiN7mv

Answer 3

Use document. getElementById()
and store it to a variable