In Nigeria, adolescents, particularly those in tertiary institutions and rural communities face persistent barriers to stigma-free HIV testing and Sexual and Reproductive Health (SRHR) services. This is due to fear of discrimination, low youth engagement, and the absence of youth-centered service models. Therefore, this study proposes the S-ITEST (4Youth by Youth) model, which is a youth-led HIV self-testing and SRHR delivery approach designed to bridge gaps in conventional systems. This 24-month implementation in Ebonyi State will be delivered through a collaboration between the Cardinal Healthcare Foundation and the Nigerian Institute of Medical Research, using clinical spaces at the Alex Ekwueme Federal University Ndufu-Alike (FUNAI), Ebonyi State. Quarterly clinic-based outreaches (3–5 days each) will target 20–25 eligible adolescents per visit, aiming to reach over 600 youths aged 14–24. Services will include confidential HIV self-testing, Sexual transmitted infection (STI) screening, PrEP education, linkage to antiretroviral care, and mobile-based retention reminders. Ethical approvals and youth consent/assent procedures will be secured. Expected primary outcomes include number tested, proportion linked to care within 30 days, and PrEP uptake. Secondary outcomes include retention and participant satisfaction. Mixed-methods data collection (program metrics and participant surveys) will assess feasibility, acceptability, and scalability. The activation of a youth-led, evidence-based testing model in a university clinic offers scalable, youth-friendly strategy to expand adolescent access to HIV prevention and SRHR services, strengthen community engagement, and advance national and global targets to end AIDS by 2030. The project will also document lessons for replication across Nigerian universities and policymakers.