Learn Danish: Jeg læser bladet i parken. - I read the magazine in the park.

Bladet means "the magazine" and is in the singular form here. The base dictionary word is et blad (a magazine). To make it plural ("magazines"), you add -e to get blade. This fits exactly with the plural rule you are practicing right now!

Why does bladet end in -et while parken ends in -en?

In Danish, the word for "the" is attached to the end of the noun. Blad is an et-word (neuter gender), so it takes -et to become bladet (the magazine). Park is an en-word (common gender), so it takes -en to become parken (the park).

Could Jeg læser also mean "I am reading"?

Yes! Danish doesn't have a separate "am doing" (continuous) tense like English does. Jeg læser translates to both "I read" and "I am reading" depending on what makes sense in the context.

Doesn't et blad also mean "a leaf"?

It does! Et blad can mean a leaf on a tree or a magazine. Since reading a tree leaf doesn't make much sense here, context tells us it means "the magazine." Conveniently, the plural for both meanings is exactly the same: blade.