無從

not to have access / beyond one's authority or capability / sth one has no way of doing

not to have / no / none / not / to lack / un- / -less

from / through / via / to follow / to obey / to engage in (an activity) / never (in negative sentence) / (Taiwan pr. [zong4]) retainer / assistant / auxiliary / subordinate / related by common paternal grandfather or earlier ancestor

not know where to start

like mice trying to pull a turtle, nowhere to get a hand grip (idiom) / no clue where to start