Boa noite, utilizei a mesma versão do bootstrap do professor, porem ficou diferente da aula.
Imagem: https://imgur.com/a/0oG4zFQ
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<meta name="viewport" content="width=device-width, initial-scale=1">
<link rel="stylesheet" href="../static/bootstrap.css">
<title>Jogoteca</title>
</head>
<body>
<div class="container">
<div class="page-header">
<h1>{{ titulo }}</h1>
</div>
<form action="/criar" method="post">
<fieldset>
<div class="form-group">
<label for="nome">Nome</label>
<input type="text" id="nome" name="nome" class="form-control">
</div>
<div class="form-group">
<label for="categoria">Categoria</label>
<input type="text" id="categoria" name="categoria" class="form-control">
</div>
<div class="form-group">
<label for="console">Console</label>
<input type="text" id="console" name="console" class="form-control">
</div>
<button type="submit" class="btn btn-primary btn-salvar">Salvar</button>
</fieldset>
</form>
</div>
</body>
</html>