For "normal" rebreather diving there’s only a need for one or two training courses — and a shed load of practice. MOD1 is the basic course with grades from 30m/100ft to 45m/150ft with some helium — largely depending on your existing skills and certifications but mostly how you do on the course. MOD2 is the deeper course requiring 50+ hours on the unit and solid skills.
AIUI that/those course(s) cannot be
commercially taught on a non-CE rebreather within the EU. There is nothing stopping you from going abroad for the course & certification and it is not illegal to bring the unit back in to the EU for personal use.
Within the EU there’s no laws against using it for personal use. It’s just a restriction on using it commercially — see the link
@Cath posted above.
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