I would focus on getting very clear about the type of roles you want and then making sure your resume matches them. For a first admin job or internship, employers usually want to see organization, communication, attention to detail, computer skills, professionalism, and reliability. Even if you have not had an office job yet, experience from school, volunteering, customer service, reception, events, or helping manage tasks for others can still be relevant.
For places to apply, you can start here:
thePros job search: https://thepros.co/search/jobs
Get.It job search: https://www.get.it/superseeker
Career resources for jobseekers: https://resources.get.it/jobseekers/
I would also apply to a mix of internships and entry-level roles such as Administrative Assistant, Office Assistant, Receptionist, Front Desk Coordinator, Data Entry Clerk, or Program Assistant. Before applying, make sure your resume is easy to read, highlights transferable skills, and shows any examples of organizing, scheduling, communication, or supporting others. Since you are looking for both internships and entry-level jobs, are you aiming more for office administration, customer-facing admin work, or support roles in a specific field like healthcare, education, or business?