Ref. No. 38 / 1095
In the name of Allah the most Gracious the mopst Merciful
The answer to your question is as follows:
Going to attend Islahi and tablighi Amaal, so that you can lead rest of your life according to Islamic teachings, is indeed a virtuous job. But if your parents are in need of your services, you have to take full care of them being at home and acting upon the faraiz and mandatory works. And when you have free time you can go for jamat too. Join the Jamat only with the intention of purifying yourself rather than others.
If you have free time and do not want to join tablighi jamat, rather you want to do another good deed or join another Islahi Jamat, then there is no problem in it too. But you must be very sincere about your Islah and inner purification.
And Allah knows best!
Darul Ifta
Darul Uloom Waqf Deoband