Getting a visa to Canada is not easy: you need to prepare a large list of documents with translations into English or French, and fill out at least three applications.

Ukrainians, as well as citizens of other CIS countries, need a visa to travel to Canada.
It is issued online and does not require an interview, as, for example, a visa to the USA. It is enough just to prepare a full package of documents, upload them in your personal cabinet and submit biometric data.
Visa can be multiple-entry or single-entry. The second option happens much less often and mainly in the case when the visa is issued under the dates of travel. With a multiple-entry visa you can stay in the country for a maximum of 6 months and enter unlimited number of times during the validity period.