I registered on the DTE portal, I have registered number but I did not fill program option and fees option because both are not opening, I did 10+2 with Maths, Physics and Chemistry.

Try contacting DTE if the portal is experiencing technical difficulties. Look at their website for the contact information and drop an email. Make sure you are accessing the right URL with a proper internet connection. Try registering with a different device and check if you are logging in with the correct credentials. You can request DTE and know if there is some other way they can help you rectify this mistake.