Hi Rahima,
There are many different communication aids available. It is important that individuals have the right kind of communication device for their needs. A Speech Pathologist, in liaison with other health professionals, can assess and provide recommendations for the best type of communication device to suit an individual, given their vision, motor skills, communication abilities and what they need to be able to do.
Follow this link to find out more about alternative and augmentative communication (AAC) aids:
https://www.asha.org/public/speech/disorders/Information-for-AAC-Users/#questions
In general terms, there are ways that you can support the people in your group with aphasia to participate, including:
I hope this is helpful.
Jessica, Stroke Connect