bash – Howto create custom service in systemd?

Running Fedora 33/34 on multiple machines. I successfully activated rc-local.service which works fine. I have couple of other scripts that I need to run in /etc/init.d/ and I created similar service files as rc-local.service, but I can’t enable it, whereas rc-local.service can be enabled/disabled/stared/stopped without any troubles.
I know, that I have an option (which I currently use) to call those scripts from rc.local file, but would rather called them separately as service. So my service file looks like this:
#cat net-scr1.service

(Unit)
Description=Network check service
ConditionFileIsExecutable=/etc/init.d/net-scr1
After=network.target 

(Service)
Type=forking
ExecStart=/etc/init.d/net-scr1 start
TimeoutSec=3
ExecStop=/etc/init.d/net-scr1 stop
RemainAfterExit=yes
GuessMainPID=no
StandardOutput=tty

(Install)
 WantedBy=multi-user.target

systemctl enable net-scr1

Synchronizing state of net-scr1.service with SysV service script with /usr/lib/systemd/systemd-sysv-install.
Executing: /usr/lib/systemd/systemd-sysv-install enable net-scr1
service net-scr1 does not support chkconfig

I moved the script out of init.d thinking maybe systemd assumes it’s an old sysv script, but no change. What should I have in my script to work properly?
My script looks like:

#!/bin/bash
EMFR=admin@server1.com
eml=admin@mydomain.com
dv0=p1p1
ipdv0=`ifconfig $dv0 | grep "inet " | awk '{print $2}'`
if ( "$1" = "stop" ); then
  cat $msg | mail $EMFR -s "$srv-shut_down-ip-$ipdv0" $eml
fi
if ( "$1" = "start" ); then
  cat $msg | mail $EMFR -s "$srv-booted_up-ip-$ipdv0" $eml  

fi

Should I include Functions from the old sysv system or something else?
Thanks