All temporary Resident Visa applicants are required to provide their biometrics, unless they have already provided them to IRCC in the last ten years in a prior application (ex: study or work permit, temporary resident visa). This requirement does not apply to applicants who are exempt from a TRV and who only require an eTA to enter Canada as visitors.
Biometrics consist of a photograph and fingerprints, which are used by the Canadian government to establish a person's identity. If you are required to provide this data, the fee is $85 CDN (170$ for a family unit); you will need to present yourself at an Application Support Center in the USA, or to a Visa Application Center (VAC) in other countries.
If you have to provide biometrics, you can still complete the online application for your TRV. To proceed with biometric data collection, IRCC will upload an instruction letter on your MyCIC account once they receive your application. Follow the instructions in the letter. Print a copy of the letter and bring it with you, as well as all required documents when you go to the biometric data collection centre. Note that processing times posted on the IRCC website do not include the time required to travel to the VAC for biometrics collection purpose.
Once collected, biometrics remain valid for ten years.
To learn more, consult: the IRCC website.