You should list 4 to 10 skills on a resume. The number of hard and soft skills you include on your resume depends on the job you want, but 4 to 10 is enough for most candidates.
If you’re applying to a job that requires a range of technical skills, such as those in software development, you’ll need to demonstrate your experience with specific software or programming languages. In this case, you should list around 10 skills or more (depending on your level of experience).
However, if you’re applying to a job that requires broader soft skills, such as those in customer service, you should list just 4 or 5 of your most relevant skills.