How to add search bar or box in shopify

search-box.liquid

<form action="/search" method="get" class="input-group search-bar" role="search">
{% comment %}<input type="hidden" name="type" value="product">{% endcomment %}
<input type="search" name="q" value="{{ search.terms | escape }}" placeholder="{{ 'Search'}}" class="input-group-field" aria-label="{{ 'Search'}}">
<span class="input-group-btn">
<button type="submit" class="btn icon-fallback-text">
<span class="icon icon-search" aria-hidden="true"></span>
<span class="fallback-text">{{ 'general.search.submit' | t }}</span>
</button>
</span>
</form>