If you wish to study Japanese at the university level, whether you need to take the Japanese paper in the CUET UG depends on the specific admission requirements of the university and the program you're applying to.

1. University Requirements: Some universities may require you to take the Japanese paper in CUET UG if they offer a specialized program in Japanese or if Japanese is a major subject. This would typically be the case for BA in Japanese or similar language-specific courses. The Japanese paper would assess your proficiency and suitability for the program.

2. General Admission: If you’re applying for a broader program where Japanese is offered as an elective or minor subject, you might not need to take the Japanese paper in CUET UG. In such cases, your admission might be based on general criteria, such as your overall CUET score and the specific subjects you've studied.

3. Contact the University: It’s advisable to check the specific admission guidelines of the universities you’re interested in. Some may offer the option to start learning Japanese from the basics, so prior knowledge or CUET paper might not be necessary.

In summary, the need to opt for the Japanese paper in CUET UG depends on the university’s specific requirements for the course you wish to pursue.