How much tax will it cost for importing if I am buying an items outside India?

i am planning to go for an internet shopping and i would like to know how much tax will it cost me again for import the items to india and I am trying to shopped from some US sites means items will be shipped from US?
i am planning to go for an internet shopping and i would like to know how much tax will it cost me again for import the items to india and I am trying to shopped from some US sites means items will be shipped from US? Items will be like clothing items thirts,caps,necklaces etc…
is it includes in the shipping cost or i have to pay an additional amount again

What tax documents do i need as a sole proprietor who is importing into india?

I have just applied for iec and i’ll be importing different types of products and raw materials into india. I will be using my residential address as office. What kind of tax documents do i need? I’ve heard that sales tax is required for those whose turnover goes beyond 10 lacs. I have no idea about taxes. I do have a pan card if that’s something you would want to know. Thank you!