You can use uto cancel. However, it usually erases the entire last line that you typed ...
Depending on the situation, you can use the following text objects:
ciwto erase and rewrite the current wordc$to erase and rewrite everything to the end of the linec^to erase and rewrite everything at the beginning of the line.ci),
. :help text-objects.
, Vim r .
- type
tje home j fj fj , jr, h