I chose Android 9 and the Samsung Galaxy S5 phone. Do I have to pay to root it here?

High Confidence (71%)
Android 9 and Samsung Galaxy S5 root access pricing

āœ… NO, rooting itself is not a paid feature for Android 9.0 because Android 9.0 and below images are already rooted by default. The root toggle feature only applies to Android 10.0 and above, where it can be changed from the UI, ADB, or HTTP API.

See Root Access and Genymotion PaaS Release Notes.

If you want, I can also clarify whether the Samsung Galaxy S5 template is available in your current Genymotion plan.