There are 3 parts to understand this:

1. Investing

You invest in a smallcase by using funds in your Kite trading account. You can either start an SIP or do a lump-sum investment. All invested smallcase constituents will be added to your Demat account.

2. Tracking

You can track your invested smallcase's performance, dividends and evaluate your portfolio under "Investments". You can see details of every stock so you know where your money is at all times.

3. Managing

You have complete control on your investment. You can add, edit or remove any stock from your smallcase anytime. You can also see & review rebalance updates, edit your SIP etc., from your "Investments".

Further Reading: