Learn Hardcore Norwegian: Jeg spiser brød.

In Norwegian, nouns that are considered uncountable or used in a general sense often appear without an article. Since brød is treated as an uncountable noun here (bread in general, not a specific piece of bread), it does not need an article.

Does Jeg spiser brød mean I eat bread or I am eating bread?

Both! Norwegian uses the same present tense form (such as spiser) for habitual actions (I eat bread) and ongoing actions (I am eating bread). Context usually makes it clear which one is meant.

Why do we use spiser instead of spise in this sentence?

Spiser is the present tense form of the verb, whereas spise is the infinitive form (to eat). In Norwegian, the same present tense form is used for all persons:

Jeg spiser (I eat / I am eating)
Du spiser (You eat / You are eating), etc.

How do you pronounce brød?

The ø sound in brød is similar to the vowel sound in the English word bird but pronounced with slightly more rounded lips. The ending d is typically softer and can sound almost silent.

Do I always have to say jeg when I talk about myself?