Hi @phr0201
TF messages define offsets in terms of translation and rotation between different coordinate frames (parent-child schema). If you want to compute the transformation between no directly connected (at the first level) frames/links you can use the tf2 ROS/ROS2 library for that, particularly the lookup transform.
If you want to see a quick visualization of the transformation between two frames within Isaac Sim, you can try the following recently created external extension (particularly the Measuring tool) 😉