You are able to add a Language under the Language Abilities section of the student profile. If you want to add an EAL status, follow this article.
Click on the green +Add button.
Select Language Ability.
It will default to the information below, but you can edit this by clicking into the fields and boxes.
Once you are happy with the information for that language, click the green Add Language Ability button.
I can't pick the right language
If the language you want to select isn't in the list, you won't be able to add a new one. You will need to pick one that most closely applies. This DfE article explains all the Languages they allow.