You may receive tax letters or other payment requests (all in Dutch) during your stay.
Everyone who is domiciled in Ghent needs to pay provincial taxes. You will receive a tax letter on your address in Ghent. You don't need to fill in any forms - you will also receive a transfer form with a set payable amount.
All adults holding a residence permit will receive an annual income declaration. Spring is traditionally tax time in Belgium, so watch out for either the 'manilla' colored envelope containing the annual income tax declaration or the provincial tax transfer form. If it's possible, the easiest way to fill in your tax form is online via Tax-on-web.
Students who didn't work, can send the tax letter back, mentioning 'not applicable'. Students who did work (employment contract) will have to fill out the tax form, but they will not be taxed on revenues from allowance or gifts from family members.
You may receive a payment request in Dutch for the Flemish Care Insurance ("Vlaamse Zorgverzekering"), which provides those who need long-term care with part or full cover of the costs of non-medical care offered by services, professional care providers or informal care providers. If you are a student of researcher (or family member) with a temporary residence permit or if you're from a state outside the EU, the EEA and not from Switzerland, you are exempt from joining the insurance and paying the tax. Just send proof of enrolment/registration at Ghent University for the current tax year.