Noobie help with Basic Hardware

Hi everyone, I will like to start making something for my cars…
1 is OBD2
2.- AEM 2
How Can I start ?
Tablet or Old cellphone any minimum required , external display
OBD2 Bluetooth reader, any can works or some preferences?
AEM 2 Can bus reader to connect to the cellphone (bluetooth or usb) Where can i order this
Thanks for your help

You are not the only one that could use this assistance to make one of these