Gdman

.form {
  position: relative;
  display: flex;
  justify-content: space-between;
  margin: 40px;
  padding: 30px;
  border: 1px solid gray;
}

.form::before {
  content: "";
  position: absolute;
  top: 0;
  left: 50%;
  transform: translate(-50%, -50%);
  display: block;
  width: 30px;
  height: 30px;
  border: 1px solid red;
  border-radius: 50%;
  box-shadow: 0 0 0 10px #fff;
  background: #fff;
  /* и ваша картинка*/
}

.btn {
  position: absolute;
  bottom: 0;
  left: 50%;
  transform: translate(-50%, 50%);
  padding: 0.5em 1em;
  box-shadow: 0 0 0 10px #fff;
  background: #f00;
  border: 0;
  color: #fff;
}

<form class="form" action="">
  <input type="text">
  <input type="text">
  <input type="text">
  <button class="btn" type="submit">btn</button>
</form>