Non-EU nationals have to check, if they need a visa to enter Latvia. The visa validity period depends on each specific case. Please, see more detailed information below.

Non-VISA countries 

• Non-EU nationals of certain countries may enter Latvia without a visa and stay in Latvia for up to 90 days in any 180-day period. Please, check the full list of the countries, whose citizens DO NOT require a visa. 
• Non-visa country citizens, who come to Latvia for a period longer than 90 days, MUST apply for a residence permit. Those citizens of non-visa countries, who are enrolled in full-time studies at an educational institution registered with the Register of Education Institutions of the Republic of Latvia, are eligible to apply for residence in Latvia on the basis of their student status. In order to enroll in part-time studies in Latvia, non-visa country citizen must first obtain a valid residence permit in a Schengen country.

For details on how to apply for a student residence permit, see information in OCMA webpage → Residence permits. Note that it may take up to several weeks to obtain a visa or a residence permit, so the application procedures should start as early as possible.