You are not too old; as the hadith says, "Seek knowledge from the cradle to the grave." Besides, many Islamic scholars started their education later.
There are physical colleges that you can attend and also there are a number of online courses; you can explore them to see what fits your needs.
Some suggestions to start your search are:
* The Islamic College in the UK (islamic-college.ac.uk)
* Al-Mahdi Institute in the UK
* Ahl al-Bayt Islamic Seminary in Chicago
* AlQaem institute
* Online ShiaStudies (onlineshiastudies.com)
* Al-Mustafa Open University in Iran (https://www.onlinestudies.com/universities/Iran/Al-Mustafa-Open-University/)
This is a very partial list. If you talk to people around you or search online you can find different programs in specific countries and see what is suitable for you, your situation, and your interests.
Best wishes with your studies!