not really working

order.html

@@ -0,0 +1,65 @@
+<header>
+    <h1>New Order</h1>
+</header>
+<nav>
+    <a href="/">back</a>
+</nav>
+<main>
+    <form method="post">
+        {{with .Order}}
+        <div>
+            <h2>Info</h2>
+            <input hidden="true" name="id" value="{{.ID}}">
+            <label>name</label>
+            <input type="text" name="name" value="{{.Name}}">
+            <label>surname</label>
+            <input type="text" name="surname" value="{{.Surname}}">
+            <label>phone</label>
+            <input type="tel" name="phone" value="{{.Phone}}">
+            <label>location</label>
+            <select name="location">
+                <option value="Kartuzy">Kartuzy</option>
+                <option value="Somonino">Somonino</option>
+            </select>
+            <label>date</label>
+            <input type="date" name="date" value="{{.Date.Format "2006-01-02"}}">
+            <label>paid</label>
+            <input type="number" name="paid" min="0" value="{{.Paid}}">
+        </div>
+        <div>
+            <h2>Basket</h2>
+            <ul>
+                {{range .Cakes}}
+                <li>
+                    <label>{{.Name}} {{.Price}}</label>
+                    <input id="cake[{{.ID}}]" type="number" min="0" name="cake[{{.ID}}]" value="{{.Amount}}">
+                </li>
+                {{end}}
+            </ul>
+        </div>
+        {{end}}
+        {{with .Catalogue}}
+        <div>
+            <h2>Catalogue</h2>
+            <ul>
+                {{range .}}
+                <li>
+                    {{.Name}} {{.Price}} <button type=button onClick="addCake({{.ID}})">add</button>
+                </li>
+                {{end}}
+            </ul>
+        </div>
+        {{end}}
+        <button type="submit">submit</button>
+    </form> 
+</main>
+
+<script>
+    function addCake(id){
+        var cake = document.getElementById("cake["+id+"]")
+        if (cake != null){
+            return;
+        }
+        console.log(cake)
+    }
+</script>