How does leaving the country work with a Spouse Visa?

Hello,

I recently received my spouse visa ( good for three years), however my farther passed away earlier this year and I would love to spend the holidays with family if possible. I know there is the "special re-entry permit" system, however I am confused on it works really. I can not find any examples of which box to check upon disembarkation.

" When you leave, check the designated box on your Embarkation and Disembarkation Card for Re-entrants (ED card) and present it with your passport and residence card to the immigration officer."

Also, does anyone know if I can only do this for once? I understand the expiration period, but unsure how many times I can exit and re-enter. Is it better to stay put?