Yes. The JioFiber router has Landline Out port in the backside for this purpose only.
When you purchase a JioFiber connection, they assign your account with a JioFiberVoice number and that's the landline number. The number also shows up on the MyJio app.
You can find all the FAQs about JioFiberVoice
here (switch to JioFiberVoice tab).
Correction: It's
JioJoin app that can be used as JioFiber Landline. JioCall app is for Jio 4G VoLTE and JioFi users.