I am new to shopfiy.I have affffded tags like Black, Blue, Green etc. Now i want to show count like
Black(12)
Blue(1)
Green(4)
My answer to a similar question might help you with this: Shopify Tags total items
To get a count of all the products with a given tag you need to loop over the products and manually count them.
For example:
{% assign collection = collections.all %}
{% for tag in collection.all_tags %}
{% assign products_count = 0 %}
{% for product in collection.products %}
{% if product.tags contains tag %}
{% assign products_count = products_count | plus: 1 %}
{% endif %}
{% endfor %}
{{ tag }} ({{ products_count }})
{% endfor %}