Man pages matching name systemd-bless-boot.service in section 8:

systemd-bless-boot.service.8.en	debian 10 / systemd
systemd-bless-boot.service.8.de	debian 11 / manpages-de
systemd-bless-boot.service.8.en	debian 11 / systemd
systemd-bless-boot.service.8.de	debian 12 / manpages-de
systemd-bless-boot.service.8.en	debian 12 / systemd-boot