Emails Not working (Gmail account) ERPNext v12.11.2

I installed ERPnext on Debian DigitalOcean Droplet.

Version
ERPNext: v12.11.2 (version-12)
Frappe Framework: v12.9.1 (version-12)

I enabled gmail account to allow less secure apps

I tested postfix via the command line and i was able to send an email via Debian command line.

Port 465, 587 are opened.

On ERPNext , when i test by sending an email, there is no response and the email is not sent.

I have gone through topics here but all are not clear and no one gives a clear and proper step.

can you share error log?

Kindly point me to the right error log:

I have:
ls /home/frappe/frappe-bench/logs/
backup.log frappe.log.14 frappe.log.3 node-socketio.log schedule.log
bench.log frappe.log.15 frappe.log.4 redis-cache.error.log web.error.log
frappe.log frappe.log.16 frappe.log.5 redis-cache.log web.log
frappe.log.1 frappe.log.17 frappe.log.6 redis-queue.error.log worker.error.log
frappe.log.10 frappe.log.18 frappe.log.7 redis-queue.log worker.log
frappe.log.11 frappe.log.19 frappe.log.8 redis-socketio.error.log
frappe.log.12 frappe.log.2 frappe.log.9 redis-socketio.log
frappe.log.13 frappe.log.20 node-socketio.error.log schedule.error.log

and:
ls /var/log
alternatives.log daemon.log.1 kern.log.1 messages syslog.3.gz
alternatives.log.1 daemon.log.2.gz kern.log.2.gz messages.1 syslog.4.gz
apt debug lastlog messages.2.gz syslog.5.gz
auth.log debug.1 mail.info mysql syslog.6.gz
auth.log.1 dpkg.log mail.info.1 nginx syslog.7.gz
auth.log.2.gz dpkg.log.1 mail.info.2.gz ntpstats ufw.log
btmp fail2ban.log mail.log redis user.log
btmp.1 fail2ban.log.1 mail.log.1 supervisor user.log.1
cloud-init.log fail2ban.log.2.gz mail.log.2.gz syslog wtmp
cloud-init-output.log fontconfig.log mail.warn syslog.1 wtmp.1
daemon.log kern.log mail.warn.1 syslog.2.gz

Also take note that when i do a send email test from the ERPNext account the log at /var/log/mail.log,

Does not Catch anything , i was thinking like POSTFIX is not well linked with ERPNext in layman view, because am not experienced in Unix stuff.