Can you get a plantar wart on your finger?
Plantar warts are, by definition, warts on the bottom of your
foot or toes. A wart appearing anywhere else on the body is not a
plantar wart, even if it's caused by one of the strains of the
human papillomavirus that's generally associated with plantar
warts.
(If you're asking if it's possible for the virus to spread from
a plantar wart to other locations on the body: yes, that's
possible. But it wouldn't be CALLED a plantar wart; if it appeared
on the palm, for instance, it would be a palmar wart.)