JSFiddle - React, Tailwind, and code Playground

HTML

<table class="table table-striped">
<thead>
        <tr>
          <th>№</th>
          <th>Прокат</th>
          <th>Сумма</th>
          <th>Интернет</th>
          <th>Сумма</th>
          <th>Печать</th>
		  <th>Сумма</th>
		  <th>Файлы</th>
		  <th>Сумма</th>
          <th>Всего</th>
         
        </tr>
      </thead>
      <div id="form1">
<tr>
	<td>
	<input type="text" class="in" id="num" name="num" value="1">

</td>
	<td>

	<button class="but" onclick="goprokat(1);">Start</button>
	<input type="hidden" name="prost" id="prost">
<button  class="but" onclick="sumprokat(1);" >Stop</button>
<input type="hidden" name="proend" id="proend"><br>
	<input class="in" type="text" id="sumprokat" name="sumprokat">	
	<input disabled class="in" type="text" name="min"><br>


	</td>
	<td><input  class="in" type="text" id="prosum" name="prosum" value="0">

	</td>

	<td>
	<button class="but" onclick="goinet(1);">Start</button>
	<input type="hidden" name="intst">
<button  class="but" onclick="suminet(1);" >Stop</button>
<input type="hidden" name="intend"><br>
	<input disabled class="in" type="text" name="suminet">	
	<input disabled class="in" type="text" name="intmin"><br>
	</td>
	<td>
<input  class="in" type="text" name="intsum" value="0">
	</td>
	<td>
	<label for="poplk">ОПЛ-K</label>
	<input onChange="pech(1);" onClick="$(this).val('')" class="pe" type="text" id="poplk" name="poplk" value="0"><br>
    <label for="poplr">ОПЛ-Р</label>
    <input onChange="pech(1);" onClick="$(this).val('')" class="pe" type="text" id="poplr" name="poplr" value="0">

	</td>
	<td><input type="text" name="psum" class="in"></td>

<td>
	<label for="foplk">ОПЛ-K</label>
	<input onChange="file(1);" onClick="$(this).val('')" class="pe" type="text" id="foplk" name="foplk" value="0"><br>
    <label for="foplr">ОПЛ-Р</label>
    <input onChange="file(1);" onClick="$(this).val('')" class="pe" type="text" id="foplr" name="foplr" value="0">

	</td>
	<td><input type="text" name="fsum"...

JavaScript

function goprokat(i){

$('#form'+i).find("input[name='sumprokat']").val('123');


}