The NEC is three kilometres east of Solihull town centre, effectively its own district around Birmingham International airport and railway station. It hosts large-scale trade shows, consumer exhibitions, concerts, and sporting events, drawing visitors from across the UK and internationally. The Resorts World complex on the site adds a casino, cinema, and hotels.
Check the NEC website for events during your visit — if there is a show running that interests you, the transport links (direct train from Birmingham New Street, motorway access) make it easy to attend. If nothing is on, there is little reason to visit the NEC itself. The area around the station is purely functional.