Let's see how you can easily mark items that are eligible for Input Tax Credits (ITC). 

While recording expenses,  just click on select ITC & select whether that particular item is eligible or ineligible for ITC.

If you are an advanced accounting user, you can also see that the GST paid for the items eligible for ITC will show up under Asset > Current Assets > Input Duties & Taxes > IGST/CGST/SGST Input ledger account: