Do I need a Profile Summary if I’m a junior? Yes! Even junior candidates benefit from a well-written Profile Summary. It will be used instead of your work experience (or projects) if available and it allows you to shape the perception of the recruiter. It should be seen as your elevator pitch, and it should highlight all the key requirements of the position you’re targeting.
Are a Profile Summary and a Cover Letter different? The easiest distinction I could offer is this: A Profile Summary is about you -> the primary goal is to demonstrate your fit for a type of role. A Cover Letter is about the company -> the primary goal is to show that you have researched the company, and explain your motivations for a specific role. The nuance may feel a bit "abstract", but when done correctly these 2 pieces are complementary.
Where should I place the Profile Summary? Always place your Profile Summary at the very top of your resume, right after your name and contact information. You want to minimize any effort on the recruiter's behalf, so they shouldn't have to scroll!
How long should a Profile Summary be? Keep it short and impactful, with 4 to 6 bullet points. Each bullet point within the Profile Summary should ideally span over a maximum of 2 lines.
Is the Profile Summary better as bullets or as a paragraph? The Profile Summary should be in bullet points. The reason is simple: that section is there to help the recruiter quickly get a sense of who you are and decide whether to keep reading. Bullet points make it much easier to scan and absorb key highlights than a block of text.