Most Modern English speakers cannot read Old English. For example, the first sentence of Beowulf:

Hwæt! wē Gār-Dena in ġeār-dagum,

þēod-cyninga, þrym ġefrūnon,

hū ðā æþelingas ellen fremedon.

hi! not discouraging other responses, but FYI, there was a similar question yesterday, so you can get started on this

• How similar is the modern Greek language with the Greek spoken in the Classical Period? Would they be able to understand each other?

edit: here's one more

• Would someone who speaks modern Greek be able to fluently communicate with, say, Leonidas I of Sparta?