To list your currently installed toolchains, run the nrfutil toolchain-manager list command:
$ nrfutil toolchain-manager list
Version Toolchain
v2.4.2 C:\ncs\toolchains\31f4403e35
v2.6.0 C:\ncs\toolchains\cf2149caf2
v2.6.1 C:\ncs\toolchains\cf2149caf2
v2.5.0 C:\ncs\toolchains\c57af46cb7
* v2.7.0 C:\ncs\toolchains\ce3b5ff664
The * indicates the currently selected (active) toolchain.