Which has better city access, University of Illinois Urbana-Champaign or UCLA?

UCLA has much better city access. It sits in Westwood, a neighborhood within Los Angeles, so students are already surrounded by restaurants, movie theaters, museums, shopping, internships, and major-event venues rather than needing to leave a college town to find them. UIUC is in Champaign-Urbana, which has solid off-campus options for students, but it does not offer the same scale, variety, or urban feel as Los Angeles.

For day-to-day life, UCLA students can walk to Westwood Village for food, coffee shops, theaters, and errands, and they have relatively easy access to places like Santa Monica, Beverly Hills, Koreatown, and downtown LA. The Metro and bus network make it possible to get around without a car, even though LA transit is not as seamless as cities like New York or Chicago. You will still deal with longer travel times and traffic, but the number of destinations is huge.

At UIUC, the immediate area is much more centered on student life. Campustown and downtown Champaign give you restaurants, bars, music spots, and local events, and the MTD bus system is very good for getting around campus and the two cities. But the overall environment still feels like a classic college town, not a major metro area with endless neighborhoods and entertainment options.

If regular city access is a real priority, UCLA offers the experience you are describing much more directly. UIUC has plenty to do nearby, but UCLA gives you everyday access to a major urban environment in a way UIUC simply does not.