1.
If a door, room, or path leads off a place or leads off from a place, you can go directly from that place through that door, into that room, or along that path.
There were two doors leading off the central room...
The treatment rooms lead off from the swimming pool...
A corridor led off to the left.
PHRASAL VERB : V P n , V P from n , V P prep
2.
If someone leads off in an activity, meeting, or conversation, they start it.
Whenever there was a dance he and I led off...
Boren surprisingly led off the most intensive line of questioning today.
= start off
PHRASAL VERB : V P , V P n (not pron)