How to improve the following architecture about communication between multiple devices ?

I have a project about managing student's attendance , I have to use Raspberry pi attached with Fingerprint Sensor. So when the teacher want to take student's fingerprint he should configure the Raspberry pi by using an android application (configuration such us : ID of FP device , what class ? what course ? etc ...) this data is sent to the server then the server will send the data to Raspberry pi that will take all student's fingerprint and send them to the server (REST) that save them in database.

I want to know if this architecture is correct I'm planning to use RESTful server and FCM that send data from android to server and from server to raspberry.

IS there any other alternative solution? because I find this architecture pretty hard to implement I guess.