If you want to create a public server here what u must do
Download half life dedicated server via this link
steam://install/90
After the download go to hlds directory by going to " settings ; local files ; browse local files "
Create a shortcut in the desktop
right click and choose properties
go to target tab and paste this
(-console +sv_lan 0 -ip xxx.xxx.xxx.xxx -port 27015 +map bounce +maxplayers 10)
make sure to leave a space and copy it without brackets.
the ip address must be your external ip address to find it out take this link
https://www.whatismyip.com
Replace it in the place of "xxx.xxx.xxx.xxx"
make sure to give firewall permissions when you start the shortcut
make sure to create a lan port in your router " youtube can show you how"
make sure to use your ip address by typing in cmd "ipconfig /all" without quotes and look for ipv4 address copy only the number and put in your router setting
If the shortcut crashes don't panic just reopen it
when you open the shortcut make sure that your ip address is your external ip address if its not type in (-ip "your external ip")
if you wan to make a password type in (sv_password "yourpassword")


good luck :)