Jambo,
Please find attached documentation on how to configure PPP (Point to Point over Ethernet) via the TELCO line commonly used for ADSL modems using Roaring Penguin PPPoE client of which newer versions of Linux use an automated shell script "pppoe-setup" to configure the PPPoE client.
For the younger generations, way back in the good old days, to connect to the internet you needed a modem & the fastest at the time was 14.4 Kbps then l8tr 28.8 Kbps then much l8tr 33.6 Kbps & then much much l8tr the fastest 56 Kbps - all of which used created a great "screeching" noise in the phone line .... modem and phone calls could not be made simultaneously until ADSL that could allow browsing the net at higher speeds and also talking simultaneously on the phone.
And fast forward ... these PPPoE instructions are also applicable for JTL (Jamii Telecom) which uses PPPoE over fiber optic cable, that is to get an internet connection as well as your public ip (business package), you first need to dialup to JTL over fiber optic cable (faiba) using PPPoE client
Please note that documentation is more than 15 years old but may still be useful.
Cheers & Enjoy!
Regards,
Ibrahim Kiptoo Kibowen
("Are you sure .... Look again ....")