install certbot:

$ wget https://dl.eff.org/certbot-auto
$ chmod a+x ./certbot-auto
$ sudo ./certbot-auto

get Certificate

sudo ./certbot-auto certonly \
--server https://acme-v02.api.letsencrypt.org/directory \
--manual --preferred-challenges dns \
-d trieu.pro -d *.trieu.pro
$ nslookup -type=TXT _acme-challenge.trieu.pro