No, it is best to use a CV (also commonly called a resume) template. Hiring managers will not reject your application for using a resume template to format your CV. In fact, they will appreciate you submitting a CV that is easy to read and includes all of the information they need to make a hiring decision.
CV templates are developed to look professional, meet industry standards, and be easily read by applicant tracking systems (ATS).
You need to make sure the content on your CV is unique to your circumstances, and that the template design is appropriate for your target job.