How to add font Calibri for FPDF in php?

Question

I have trying to add a Calibri font. I have tried the following:

$pdf->SetFont('Calibri','',9);

However, when I try to run it, I got this error:

Message: FPDF error: Undefined font: calibri

I have trying to add a Calibri font. I have tried the following:

$pdf->SetFont('Calibri','',9);