Here's a step by step to get you started;
1) Buy a game hosting from any company, I'd suggest the ones listed here;
https://sampforum.blast.hk/showthread.php?tid=189169
2) Once they emailed you the CPanel login details, login the CPanel.
3) There should be an FTP login details emailed to you, or try poking in the CPanel for it.
4) ****** FileZilla, install it and login using the FTP login details provided.
5) Transfer your Game Mode to the host's FTP thing, wait for the process to complete.
6) There should be an option in the CPanel which allows you to edit your server.cfg file, edit it.
7) If your given port by the host company is ex; 7777 edit the port in server.cfg to 7777, and if the host is linux, change the plugins to .so
And you're all set, try launching the server and see if it works, if anytime you'd like to edit your pawno, edit it normally on your computer and transfer the newly edited to your host's FTP.