[Kells]

first you need to Host your Server So PEople Can see it At samp and You will Have fixed Ip
If You didn't You can Portforward
And if u Know all this
In case you mean You runned The :Samp-server.exe and opened samp And didn't find it here a solution
After opening Samp-server.exe as you did go to Samp.exe and push On Add server Button Then Do
:{your Port}

EXAMPLE ---> :7777 (if the Port is 7777)
And remember people won't see your server
hope this helps