Can I trade today using the profits made from yesterday's sale proceeds?

Your fund balance will not include any intraday profits if they are not settled by the exchange. The settlement of funds will happen on the next trading day i.e T+1 for futures & options and after 2 trading days (T+2) for equity.

However, you can continue to see the funds from intraday profits in the closing balance in the cash ledger.

For example:

Suppose you buy stocks worth Rs. 5,00,000 on Monday and sell them on the same day for Rs 5,20,000. You have made a profit of Rs. 20,000. Note that since this is an equity trade the settlement will happen on T+2 i.e. trade day + two trading days. In this case, Rs. 5,00,000 will be available immediately for other transactions. However, the profit of Rs. 20,000 will be available for either withdrawal or to use towards other trades in your funds only on Wednesday as per the equity settlement cycle of T+2 days. In case the settlement day is a holiday, the intraday profits will be available on the next trading day.

If you use these unsettled funds for your trades, a margin penalty may be levied by the Exchange.