Spend a morning or afternoon walking around Lake Merritt and the great sights and shops along the way.
https://www.visitoakland.com/blog/post/top-things-to-do-in-lake-merritt/

Friday Nights at Oakland Museum of California:

Every Friday night, 5–9 pm Bars accept cash and credit. Prices vary for Off the Grid food trucks.

Get your Oakland groove on at Friday Nights at OMCA with after-hours Museum access, Off the Grid food trucks, beer, wine, music, and more!

from website: The Oakland Museum of California (OMCA) is one of the top-rated Bay Area museums to explore California art, history, and natural sciences. Recognized as one of the best things to do with kids in Oakland or the entire San Francisco Bay Area with kids, we're really for everyone from serious museum buffs to international visitors. Our collections rank us as one of the top science, history, and art museums in the East Bay, as well as the greater San Francisco Bay Area. We're at 1000 Oak Street, Oakland, California, convenient to BART.