Hello,
Taxability of UAE LLC would depend whether it is a pass through entity or an opaque corporate entity in UAE.
If it is a corporate entity then you need to pay tax in India only if you receive salary or dividend from such entity and not otherwise.
If you declare dividend, then tax needs to be paid at the time of declaration irrespective of when you received it in India.
As mentioned above if you are a shareholder and the entity is a corporate then tax liability would appear only when the corporate declare dividend.
Yes Pvt. ltd. co. can invest in Dubai co. but generally it is not advisable to do so due to some FEMA related issues hence it is advisable to invest in individual capacity.
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