No English at this time.
This language with no Latin roots, only Germanic.
No luck for who wants to learn Latin!
Fæder ure þu þe eart on heofonum, sie þin nama gehalgod. To becume þin riċe, geweorþe ðin willa, on eorðan swa swa on heofenum. Urne gedæġhwamlican hlaf sele us todæġ...
No England, only Britannia (adj. Britannicus)
These words of heroism, from "The Battle of Maldon" describing the defence of Wessex against the Danes, should be known by any patriotic English person. They encapsulate the doggedness of the English in defeat.
Bryrtwold maþelode, bord hafenode (Se wæs eald geneat); æsc acwehte He ful baldlice beornas lærde: "Hige sceal þe heardra, heorta þe cenre mod sceal þe mare, þe ure mægan litlað."
Byrtwold spake, he raised his shield aloft (He was an old loyal retainer) and brandished his spear. Full boldly he spake to his men: "Our hearts must grow resolute, our courage more valiant, Our spirits must be greater, though our strength grows less".
"Here lies our lord, all hewn down The good man in the dust. Long may he mourn Who from this war-play seeks now to withdraw. I am advanced in years: I do not desire to be taken away,
But here by my liege lord, by that most blessed of men Mean I to lie." Ac ic me be healfe, minum hlaforde, be swa leofan man, licgan ðence.
I live in Kent, not far from the village of Aylesford where Hengist and Horsa defeated Vortigern in battle in AD 455. Horsa died, but Hengist survived to set up a Jutish kingdom in Kent. The village has a restaurant called the Hengist in his name, and a Carmelite Priory which was established in 1242, destroyed in Tudor times and revived in the 20th Century. Worth a visit.
Does this mean I am currently speaking English, or that I have the ability to speak English, or both?
I know I shouldn't rely on Google translate, but I entered the English "I speak English" and was told the Latin was "Linguam Anglicam loquor", which makes sense to me when earlier in the course we have seen Latin translated by linguam Latinam (in the accusative case). On the other hand, when I entered "I am speaking English" in the hope that I'd get back "Ego Anglice loquor" I was returned utter nonsense, so I feel none the wiser.
Anglice didn't exist in the Roman times, so it solves your question:
For the language, use either "lingua anglica" (without the English uppercase), or "anglica", but when you want to use it to say "I speak", as we learned here, you have to use the adverbialised adjective "anglice".
I think it means you know how to speak English, or, you are speaking in English right now (as no -ing form in Latin), depending on the context.