The goal of this clinical study is to look at how lenacapavir (LEN) passes through the body and to assess the safety of LEN and emtricitabine/tenofovir disoproxil fumarate (F/TDF) for prevention of HIV in the cisgender women in the US. The primary objectives of this study are: 1) to characterize the pharmacokinetics (PK) of LEN in United States (US) cisgender women; 2) to evaluate the safety of LEN and F/TDF for pre-exposure prophylaxis (PrEP) in US cisgender women; and 3) to evaluate the general acceptability of LEN injections and oral F/TDF in US cisgender women.