Yes, you can participate in both state and All India counseling simultaneously. If you secure a college seat in the second round of state counseling, you are still eligible to participate in the All India Counseling (AIQ) round. However, there are a few things to keep in mind:

1. **Seat Withdrawal**: If you accept a seat through state counseling but later get a better option through AIQ, you can withdraw from the state seat by surrendering it as per the respective state’s guidelines. This is usually allowed before a specified deadline, and it's essential to follow the correct procedures to avoid penalties or being barred from further counseling rounds.

2. **Document Handling**: Since counseling requires document verification, ensure that you have multiple copies of all necessary documents and certificates so that you can submit them in both state and AIQ counseling if needed.

3. **Payment of Fees**: Be mindful of fee structures. You may need to pay fees during state counseling, and if you later opt for an AIQ seat, ensure you withdraw properly to avoid forfeiting the fees.

In short, participation in both state and AIQ counseling is permitted, but make sure you manage the process efficiently to secure the best seat possible without complications.