I want to track a phone. Do u still need to sign into iCloud in order to track th phone?

Yes.

In Find Devices on iCloud.com, click All Devices. Select the device you want to locate. The name of the device appears in the center of the Find Devices toolbar ...

Locate a device in Find Devices on iCloud.com

To clarify, you need only “partially” sign-in.

(w/o using the 2FA Verification Code which would otherwise be required)

https://icloud.com/find