Use Bootstrap Icons SVG font: install via npm or CDN and apply with class bi bi-icon-name.
Bootstrap Icons
<!-- Install -->
npm install bootstrap-icons
<!-- Or CDN -->
<link rel="stylesheet" href="https://cdn.jsdelivr.net/npm/bootstrap-icons@1.11.3/font/bootstrap-icons.min.css">
<!-- Usage -->
<i class="bi bi-house"></i>
<i class="bi bi-person-fill"></i>
<i class="bi bi-envelope"></i>
<i class="bi bi-github"></i>
<i class="bi bi-star-fill text-warning"></i>
<!-- Sized icons -->
<i class="bi bi-heart" style="font-size: 2rem;"></i>
<i class="bi bi-heart fs-1"></i>
<!-- Icon in button -->
<button class="btn btn-primary">
<i class="bi bi-plus-circle me-1"></i> Add Item
</button>
<!-- SVG usage (no font needed) -->
<svg class="bi" width="32" height="32" fill="currentColor">
<use href="bootstrap-icons.svg#heart"/>
</svg>