One piece of advice first

Rules change, and how they apply depends on your situation (country of residence, income, legal form of activity). Below is a list of questions, not ready-made answers. Put them to an accountant or the relevant authority.

What to check in every country

AreaQuestion
Registrationat my level of income, do I have to register a business or notify an authority?
Income taxhow and when do I declare income from commissions and sales?
VATdo I have to register for VAT and how do I account for sales to customers?
Consumer protectionwhat return rights do my customers have, and I as a buyer?
Advertisingwhat may I say about the products (without attributing healing properties)?
Personal datahow do I protect customers' data in line with GDPR?
Availabilitydoes dōTERRA operate in my country, and on what terms?

Pointers for selected countries

Advertising and social media

Don't attribute healing properties to oils or promise health results. Rules differ between countries, but caution protects both you and your audience. Always state that you are an independent Wellness Advocate.