It depends on how far you'd like to drive for a day trip. From Vancouver, you could head north on the Sea to Sky and hop between lakes around Squamish (Browning, Alice, Brohm). They all have small rainbow and cutthroat trout in them, but combining that with some hiking etc it could be a good day? The lakes have plenty of shore access.
Heading toward the Fraser Valley, Hicks Lake at Sasquatch Provincial Park has a variety of species (rainbow trout, cutthroat trout and kokanee) and they should all be hanging around in the shallows close to shore now. Shore fishing is possible with a bit of hiking involved along the lake shoreline from the day use area.
Chilliwack River is about to reopen on July 1st so you could try fishing for chinook salmon there.
Heading into Interior BC, there are several lakes where shore fishing is possible. Tunkwa, Leighton and Logan Lake all have some kind of shore access and it's definitely not impossible to catch those rainbow trout from shore as long as the wind cooperates. Marquart and Lundbom Lake just outside of Merritt also have shore fishing spots, but from what I've heard Lundbom is getting quite a bit of algae now.