5V Relay Wiring

Hello All,
I am currently working on an automated system that will use a 5V relay to turn a pump on and off. The problem I have run into is that I am currently using the 3.3V as well as the 5V connections on my Arduino to run a screen for outputs. How would I be able to use a relay without the proper connections to create a circuit for the relay. I have considered using a second Arduino, to work with the main Arduino, which will manage the screen system, and the second one can work the relay system. Please let me know if there is any way to avoid using a second Arduino with wiring. Thank you for your help!

Breadboards can be of help.

See how power is sent to the breadboard and then distributed to various thinges?