ThankQ !
For how many days does one take it?
The definitive article is Review of the Emerging Evidence Demonstrating the Efficacy of Ivermectin in the Prophylaxis and Treatment of COVID-19.
For treatment, it seems you take it twice, with an off-day in between.
Mind you, I'm not a doctor and I'm not prescribing this for you. I'm just pointing out some highlights from the article. For prophylaxis, the article has many different regimens, one example being to take two doses with two off-days between, and do this once monthly. (See pages 10 and 11)