nachher
later / afterwards
At a later point in time; after something that is happening right now or has just been mentioned.
Wir gehen jetzt einkaufen und kochen nachher zusammen.
We're going shopping now and will cook together later.

later / afterwards
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later / afterwards
At a later point in time; after something that is happening right now or has just been mentioned.
Wir gehen jetzt einkaufen und kochen nachher zusammen.
We're going shopping now and will cook together later.

The word 'nachher' (later/afterwards) is a compound of 'nach' (after) and 'her' (toward here/from then). It literally means 'after this point in time' and always refers to a later moment that follows the present or a stated point in time.
Lass uns zuerst die Hausaufgaben machen, nachher können wir spielen.
Let's do the homework first; later we can play.
'Nachher' (later/afterwards) is an adverb and can stand in different positions in the sentence. If it is in position 1, the verb follows directly. But it can also stand after the verb and the subject.
Nachher gehe ich ins Kino.
Later I'm going to the movies.
'Nachher' (later/afterwards) is used very often in spoken language to talk about the near future. It often sounds more natural than more formal expressions.
Ich rufe dich nachher zurück, ich bin gerade beschäftigt.
I'll call you back later; I'm busy right now.
then
'dann' and 'nachher' can both mean that something happens later. 'dann' often shows the sequence: first something happens, then the next step comes. 'nachher' more often refers to a later point in time after now or after a mentioned situation. Learners may confuse the words because both point forward in time. In practice: for a clear sequence, 'dann' works very well; for 'later the same day' or 'afterwards', 'nachher' often sounds more natural.

Sarah ruft dich nachher an, wenn sie zu Hause ist.
Sarah will call you later when she's home.
Ich gehe zuerst zum Arzt und dann direkt zur Arbeit.
I'm going to the doctor first and then straight to work.