"At school French lessons are not given."
Translation:Okulda Fransızca dersi verilmiyor.
"Verilmez" is present simple whereas "verilmiyor" is present continuous.
Your guess is correct. Keep in mind that present continous sometimes carries the meaning of present simple in Turkish.
Using "verilmez" (present simple) in this case can also sound like you're making the subjective statement of "French lessons must not / should not be given at school." but this is advanced semantics for new learners. This meaning can be understood from either context or pronuciation.