If you have vitamin d deficiency will the covid-19 vaccine still produce a memory response in t cells?

Yes. Vitamin D deficiency is unlikely to interfere with your immune response to Covid vaccine. Vitamin D deficiency is easily correctable by taking Vitamin D3 capsules. You may safely take 4000 units/day.

Although optimal Vitamin D levels are important for multiple immune reactions, a low normal level would not be expected to compromise the protective effect of COVID-19 vaccines employed in the USA. It is helpful to know your true serum level, and your physician can order appropriate testing.