<font-awesome-icon icon="fa-solid fa-angle-down" />
<FontAwesomeIcon icon="fa-solid fa-angle-down" />
.my-icon::before {
font: var(--fa-font-solid);
content: "\f107";
}
<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 384 512" style="width: 30px;height: 30px;fill: black">
<path d="M192 384c-8.188 0-16.38-3.125-22.62-9.375l-160-160c-12.5-12.5-12.5-32.75 0-45.25s32.75-12.5 45.25 0L192 306.8l137.4-137.4c12.5-12.5 32.75-12.5 45.25 0s12.5 32.75 0 45.25l-160 160C208.4 380.9 200.2 384 192 384z"/>
</svg>
<i class="fa-solid fa-angle-down"></i>