A floating label sits inside the field and shrinks to the top edge once it has a value. Wrap the control and label in .form-floating, control first, and give the control a non-empty placeholder.
<link rel=stylesheet href="https://cdn.jsdelivr.net/npm/bootstrap@5.3.8/dist/css/bootstrap.min.css">
<div class="p-3 row g-2">
<div class="col"><div class="form-floating"><input class="form-control" id="fMail"
placeholder="x"><label for="fMail">Email address</label></div></div>
<div class="col"><div class="form-floating"><input class="form-control" id="fCity"
placeholder="x" value="Penang"><label for="fCity">City</label></div></div>
<div class="col"><div class="form-floating"><select class="form-select" id="fLand">
<option>Malaysia</option></select><label for="fLand">Country</label></div></div>
</div>