Use fprintd https://wiki.archlinux.org/title/Fprint

sudo

in /etc/pam.d/sudo just add to the top:

auth      sufficient pam_fprintd.so

polkit

For GNOME prompts, first install pam-fprint-grosshack if you want to be able to user fingerprint or a password and add to the top of /etc/pam.d/polkit-1:

auth		sufficient  	pam_fprintd_grosshack.so
auth		sufficient  	pam_unix.so try_first_pass nullok

gdm

GDM has built in fprintd support