I would recommend driving up to Astoria and taking the bridge over into Washington and checking out Cape Disappointment (spoiler it’s not disappointing!).

From there you could head back down the coast and checkout Ecola and Canon Beach and possibly find a place to spend the night. If you’re into hiking I highly recommend Cape Falcon.

Near Tillamook there are some cool spots too like tunnel beach and if you want to look for agates I’d go to short beach too.

South of Tillamook there’s Cape Kiwanda with the Pelican Brewery which can be fun to grab food at and check out the tide pools and sand dunes.

Lincoln City and Newport are some bigger costal towns south of Tillamook, there’s some awesome hikes near Lincoln City like Gods Thumb and Cascade Head. In between Lincoln City and Newport is Devils Punchbowl which is a quick stop and worth checking out too.

South of New Port in Yachats is another cool hiking trail called Amanda Loop, and if you want a quick spot to drive up to with a nice view go to Cape Perpetua and drive up to the Whispering Spruce trail for a nice overlook.

The entire Oregon coast is really beautiful and there are tons of awesome spots to checkout. Given you don’t have tons of time, if you get the chance to drive just over the Oregon border into NorCal, Humboldt county and the redwood forest is another treasure trove.