<form class="row g-3 needs-validation" novalidate>
  <div class="col-lg-6">
      <label for="validationCustom01" class="form-label">First name</label>
      <input type="text" class="form-control" id="validationCustom01" value="Mark" required>
      <div class="valid-feedback">
        Looks good!
      </div>
    </div>
    <div class="col-lg-6">
      <label for="validationCustom02" class="form-label">Last name</label>
      <input type="text" class="form-control" id="validationCustom02" value="Otto" required>
      <div class="valid-feedback">
        Looks good!
      </div>
    </div>
    <div class="col-lg-6">
      <label for="validationCustomUsername" class="form-label">Username</label>
      <div class="input-group has-validation">
        <span class="input-group-text" id="inputGroupPrepend">@</span>
        <input type="text" class="form-control" id="validationCustomUsername" aria-describedby="inputGroupPrepend" required>
        <div class="invalid-feedback">
          Please choose a username.
        </div>
      </div>
    </div>
    <div class="col-lg-6">
      <label for="validationCustom03" class="form-label">City</label>
      <input type="text" class="form-control" id="validationCustom03" required>
      <div class="invalid-feedback">
        Please provide a valid city.
      </div>
    </div>
    <div class="col-lg-6">
      <label for="validationCustom04" class="form-label">State</label>
      <select class="form-select" id="validationCustom04" required>
        <option selected disabled value="">Choose...</option>
        <option>...</option>
      </select>
      <div class="invalid-feedback">
        Please select a valid state.
      </div>
    </div>
    <div class="col-lg-6">
      <label for="validationCustom05" class="form-label">Zip</label>
      <input type="text" class="form-control" id="validationCustom05" required>
      <div class="invalid-feedback">
        Please provide a valid zip.
      </div>
    </div>
    <div class="col-12">
      <div class="form-check">
        <input class="form-check-input" type="checkbox" value="" id="invalidCheck" required>
        <label class="form-check-label" for="invalidCheck">
          Agree to terms and conditions
        </label>
        <div class="invalid-feedback">
          You must agree before submitting.
        </div>
      </div>
    </div>
<button class="btn btn-primary" type="submit">Submit form</button>
</form>