Linear B was used for writing the earliest forms of Greek used by the Mycenaean civilization.
For a Unicode Font, download Aegean from this page.
For a Unicode keyboard, go to this page.
Another input option is a character picker:
https://tomer.github.io/characterPicker/#?load=0x10080-linear_b_ideograms.json
https://www.cs.tut.fi/~jkorpela/fui.html8
For online resources for studying Linear B, see e-ni-jo-te.
(I recommend you not use the old non-Unicode Clark fonts which map Linear B to Latin, as everyone should be using Unicode for text exchange these days)
For a Unicode Font, download Aegean from this page.
For a Unicode keyboard, go to this page.
Another input option is a character picker:
https://tomer.github.io/characterPicker/#?load=0x10080-linear_b_ideograms.json
https://www.cs.tut.fi/~jkorpela/fui.html8
For online resources for studying Linear B, see e-ni-jo-te.
(I recommend you not use the old non-Unicode Clark fonts which map Linear B to Latin, as everyone should be using Unicode for text exchange these days)