I have kidney stone and osteoporosis what calcium supplement i s best if any?

two are okay: Calcium citrate and calcium lactate. Both ultimately could increase citrate in urine which is a good thing. But need to have 24 hour urine follow up to make sure calcium excretion in urine is not substantial.

Need workup: occurrence of kidney stones, needs evaluation to find out the underlying etiology, likely primary hyperparathyroidism, hypercalciuria etc. Recommendations will depend upon findings of the investigation. Recommend evaluation by endocrinologist