Rome's basilicas are simultaneously historic monuments, places of worship, and sites of Christian memory. A visit requires both context and attention to the liturgical schedule.
Do not treat basilicas as museums
Celebrations may affect access and the route. Maintain conduct appropriate to the space.
Distinguish history from tradition
Some places are archaeologically documented; others are connected to religious traditions. Both can be explained without confusing them.
Practical note
Information about tickets, schedules, transport, and access can change. Check official sources close to your travel date.