How to setup or configure sendmail in ubuntu 22.04 with custom smtp relay

When I searched for configuring sendmail on ubuntu I din't get any clear answer, each of them assume I know what they are talking about,

I just wanna know how to configure sendmail with custom smtp relay, like smtp-relay.brevo.com and how to test it

Thanks

Need port 25 dan 587 if you using docker container

1. apt install sendmail sendmail-bin mailutils
2. mkdir -m 700 /etc/mail/authinfo
3. nano /etc/mail/authinfo/smtp-auth

AuthInfo:smtp-relay.brevo.com  "U:your-email" "P:your-smtp-key"

4. makemap hash /etc/mail/authinfo/smtp-auth < /etc/mail/authinfo/smtp-auth
5. chmod 600 /etc/mail/authinfo/smtp-auth.db
6. nano /etc/mail/sendmail.mc

....
dnl #
dnl # Defining Gmail Smarthost for sendmail
define(`SMART_HOST',`[smtp-relay.brevo.com]')dnl
define(`RELAY_MAILER',`esmtp')dnl
define(`RELAY_MAILER_ARGS', `TCP $h 587')dnl
define(`ESMTP_MAILER_ARGS', `TCP $h 587')dnl
define(`confAUTH_OPTIONS', `A p')dnl
TRUST_AUTH_MECH(`EXTERNAL DIGEST-MD5 CRAM-MD5 LOGIN PLAIN')dnl
define(`confAUTH_MECHANISMS', `EXTERNAL GSSAPI DIGEST-MD5 CRAM-MD5 LOGIN PLAIN')dnl
FEATURE(`authinfo',`hash -o /etc/mail/authinfo/smtp-auth.db')dnl
dnl #
dnl # Default Mailer setup
MAILER_DEFINITIONS
MAILER(`local')dnl
MAILER(`smtp')dnl

7. make -C /etc/mail
8. service sendmail reload
9. echo "This is a test for sendmail gmail relay" | sendmail your-email@gmail.com