The Beach at Repulse Bay is probably one of the best we have in Hong Kong in terms of beach size, sand quality, access to public transportation and area restaurants and shopping. This is a nearly 300 metre long stretch of seaside nuzzled up against the southern shores of Hong Kong Island. It is one of a series of beaches including Deep Water Bay Beach (to the northwest), Middle Bay Beach and South Bay Beach (to the southeast) and by far the most interesting.
You can visit Repulse Bay beach by public bus or taxi or by foot walking the Seaview Promenade from Deep Water Bay. You'll find promenade and pier areas on both ends of the beach with park benches. Alongside the beach there is a shopping arcade called the pulse, where there are a handful of alfresco restaurants, coffee shop, ice-cream as well as s sports gear and other retailers.
The beach itself is pretty good. In addition to the nice sand quality, there are several rows of trees towards the back of the beach providing a bit of shade on sunny days. You'll find expected range of facilities including public toilets, changing stations and life guard stations, BBQ pits (unavailable during the pandemic). Swimming is good at Repulse Bay Beach with normal sea conditions and views are nice with favourable visibility.
Do note that Repulse Bay Beach can be very crowded during warmer weather weekends and public holidays during non-pandemic times. As such, you may find it more favourable to opt for a second beach like nearby Deep Water Bay Beach if there are too many people here. Otherwise, this is a very good beach to spend time with friends or family on Hong Kong Island.