Delphi 11 work with TEdgeBrowser, get HTML element

Question

There is some page, which contains:

<input type="input" id='input_value' ...>
<button id='btn_find' ... >
<input type="checkbox" name="chbox1" ...">

For each string from memo1, I want:

1. put the string in input_value,

2. click on btn_find,

3. wait several seconds (until completed page loading or 3 seconds)

4. if string exist, the chbox1 appears we must click on it

5. if string doesn't exist, the chbox1 invisible we must in memo2 lines add string; I use TEdgeBrowser

   for i := 0 to memo1.lines.Count - 1 do    begin
    js:='document.getElementById("input_value").value="'+memo1.lines[i]+'"';
    EdgeBrowser1.ExecuteScript(js);
    EdgeBrowser1.ExecuteScript('document.getElementById("btn_find").click()');
    Delay(3000);
    // here I must check if the chbox1 visible 
   if {chbox1 visible} then
      EdgeBrowser1.ExecuteScript('document.getElementsByName("chbox1")[0].click()')
      else memo2.lines.add(memo1.lines[i]);
    end;