I'm trying to make app for sending personal information via bluetooth to Arduino but while making app I got error

Or any one help me for how to build app for transmitting personal information like ( name , contact number )
In Arduino via bluetooth ... And app screen get refresh.

Please help me in this because I don't now how to use and all I watched videos regarding this but not that much helpful .. so please help me :pray:

Please download and post each of those event block(s)/procedures here ...
(sample video)