Sorry so long to reply.
#needs squashfs-tools openssl:
tce-load -wi squashfs-tools openssl
#first, modify ld.so.conf and config:
dpm config
#now search or install package:
dpm -s geany
dpm -wi geany
#If necessary, select a faster mirror:
dpm mirror unitedstates
or dpm mirror, then type the country
or MIRROR=http://mirror.nju.edu.cn/debian/ CODENAME=buster SUBDIV=main dpm config
or MIRROR=http://mirror.nju.edu.cn/debian/ dpm -wi xxx
#convert deb to tcz
sudo deb2tcz.sh xxx.deb
latest dpm 1.1.2: