Remélem, hogy holnap visszavihetem a kávéfőzőt a csomagolással.

I hope that I can take the coffee maker back tomorrow with its packaging.

Breakdown of Remélem, hogy holnap visszavihetem a kávéfőzőt a csomagolással.

• holnap: tomorrow
• az: the
• hogy: so that
• remélni: to hope

Questions & Answers about Remélem, hogy holnap visszavihetem a kávéfőzőt a csomagolással.

Why is it Remélem and not Remélek?

Because Hungarian usually treats the hogy-clause here as if there were an implied object: (azt) remélem, hogy... = I hope that...

So remélem is the definite 1st person singular form of remél.
A native-speaker way to think of it is:

• Remélem = I hope it / I hope that...
• Remélek = the indefinite form, which is not the normal choice in this sentence

So Remélem, hogy... is the expected wording.

What does hogy do here? Is it like English that?

Yes. hogy introduces a subordinate clause, very much like English that:

• Remélem, hogy holnap... = I hope that tomorrow...

In English, that is often optional. In Hungarian, hogy is very common and natural here. In casual speech it can sometimes be omitted, but keeping it is standard and clear.

How is visszavihetem built up?