git format-patch -1 <sha>
  git apply --stat file.patch # show stats.
  git apply --check file.patch # check for error before applying.
  git am < file.patch # apply the patch finally.

https://mirrors.edge.kernel.org/pub/software/scm/git/docs/git-format-patch.html

For generating the patches from the topmost commits from a specific sha1 hash:

git format-patch -

The last 10 patches from head in a single patch file:

git format-patch -10 HEAD –stdout > 0001-last-10-commits.patch

https://stackoverflow.com/questions/6658313/generate-a-git-patch-for-a-specific-commit