Thank you so much, that really helped. Here is the working code in case anyone else needs it as reference.
//global variables
let button;
let inp;
function setup() {
inp = createInput('');
inp.position(100,100);
newInput = inp.input(myInputEvent);
button = createButton('click me');
button.position(19, 19);
button.mousePressed(changeText);
createCanvas(500, 500);
}
function myInputEvent() {
var myInput = this.value();
return myInput;
}
function changeText(){
text (inp.value(), 100, 200);
}