Non EU citizens wishing to work in Estonia must apply for a residence permit for employment which is issued for a period of guaranteed employment in Estonia by an employer.
Nationals of some countries can visit Estonia for up to
three months without a visa, these are listed at the website of the Estonian Citizenship And Migration Board
If you intend to visit Estonia, on holiday, a business trip, to study, work, volunteer or as an emigrant you should get up to date and accurate information from the official website of the Estonian Citizenship And Migration Board