Learn Croatian: Zaboravljajući na svaku obavezu, odvoji vrijeme za sebe. - Forgetting about every obligation, set aside time for yourself.

The pronoun sebe (self) is a reflexive pronoun used whenever the object of the action is the same as the subject. The hidden subject here is "you" because odvoji is a command directed at you. Since you are setting aside time for yourself, Croatian requires the reflexive za sebe rather than za tebe.

What case is sebe in this sentence?

It is in the accusative case, which is required here by the preposition za (for). The genitive and accusative forms of this reflexive pronoun are identical (sebe), but you can tell it is accusative because of the preposition.

What kind of word is Zaboravljajući?

This is a present verbal adverb, which you can recognize by the -ći ending. It is formed from the imperfective verb zaboravljati (to forget) and translates to "forgetting" or "while forgetting". It is used to show that this background action is happening at the exact same time as the main verb.

Why does the sentence use na svaku obavezu instead of a preposition like o (about)?

In English you "forget about" something, but in Croatian, the verbs zaboraviti and zaboravljati are usually paired with the preposition na followed by the accusative case. So na svaku obavezu is the standard, natural way to express forgetting about every obligation.