Neutrinoless double-beta decay($0 ubetabeta$) decay is a hypothetical process that violates lepton number, and whose observation would unambiguously indicate that neutrinos are Majorana fermions. In the standard inverted-ordering neutrino mass scenario, the minimum possible value of m$_{betabeta}$ corresponds to a half-life around 10$^{28}$ yr for $0 ubetabeta$ decay in $^{76}$Ge, which is the target of the next generation of experiments. The current limits of GERDA and textsc{Majorana Demonstrator} indicate a half-life higher than 10$^{26}$ yr. These experiments use high-purity germanium (HPGe) detectors that are highly-enriched in $^{76}$Ge. They have achieved the best intrinsic energy resolution and the lowest background rate in the signal search region among all $0 ubetabeta$ experiments. Taking advantage of these successes, a new international collaboration - the Large Enriched Germanium Experiment for Neutrinoless $betabeta$ Decay (LEGEND) - has been formed to build a ton-scale experiment with discovery potential covering the inverse-ordering neutrino mass range in a decade, following a phased approach. This first part of LEGEND proceedings describes GERDA and textsc{Majorana Demonstrator} capabilities and the general plan of LEGEND to reach the goal, while the second part is focused in the status of the first stage of LEGEND, LEGEND-200.
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