You are covered from arrival, with no waiting period

New olim are registered with a health fund (kupat cholim) on arrival and there is no waiting period, unlike returning residents who face a waiting period or a redemption fee. Register with a kupah within your first weeks to lock in supplemental-benefit eligibility without waiting periods.
During the absorption-basket period (roughly your first six months) as an oleh receiving absorption support, the Ministry of Aliyah covers your health-insurance contribution. Bituach Leumi applies this exemption automatically; you do not file for it. Confirm the exact duration at your absorption meeting, because once the covered period ends you pay the standard health contribution like any resident, and olim are sometimes surprised by the first deduction.
Choosing a kupah
Israel has four health funds: Clalit, Maccabi, Meuhedet, and Leumit. The basic health basket is identical across all four by law, so the differences are in supplemental insurance tiers, clinic locations near you, and English-language service availability. For olim, proximity and language service often matter more than the marginal plan differences.
The decision is reversible: you can switch funds, so do not treat the week-one registration as permanent. Register with a reasonable choice now, and revisit it once you have settled.
This is exactly where a skill goes deeper than a course can. The israeli-hmo-navigator skill compares the four funds, their supplemental tiers, and referral processes for your specific situation. Install it when you are ready to choose or switch, and ask it about the funds available where you live.