Welcome to The AnswerBank.
As this site is UK-based, we don't have many 'regulars' in Canada. (Indeed, to the best of my knowledge, I don't think that there are any at all). So I doubt that anyone here will be able to answer your question. (Sorry!)
You might be able to get a bit of insight though from one or more of the following links:
CBSA's own website:
https://www.cbsa-asfc.gc.ca/job-emploi/recruitment-recrutement/job-description-emploi-eng.html
[NB: Please note that other pages on the site are currently showing this message: "The Officer Trainee Developmental Program selection process is now closed"]
132 reviews from employees on Indeed.com:
https://ca.indeed.com/cmp/Canada-Border-Services-Agency/reviews
The latest CBSA employee survey results:
https://www.tbs-sct.canada.ca/pses-saff/2022/results-resultats/en/bq-pq/index/83
The Workplace, on Stack Exchange, where you might be able to make contact with people with experience of working for CBSA:
https://workplace.stackexchange.com/
Quora, where there might be more Canadians than here on The AnswerBank:
https://www.quora.com/