a raspberry is a complete linux computer. you can do a lot of user interface programming with it. it costs around $50
an arduino is a microcontroller, with a lot less power in it, and a clone can cost $3
they really are not the same devices.
the arduino will be easier to interface with sensors and devices, at an electronic level
the raspberry will be easier to deal with complex user interface on a big lcd screen.
I would use both devices for your application: the raspberry to make the user interface,
and the arduino to deal with I/Os. they can talk to each other using i2c or even ethernet (with esp32 or esp8266)