Sell Items Online
Dog Walking Service or Pet Sitting
Freelancing on Fiverr
There are plenty of options available including designing logos and website banners, creating digital graphics such as infographics and presentations, doing voiceovers for audio files like podcasts (and other things), writing customized blog posts & articles, transcribing videos into text format among many others.
Be A Local Travel Guide
One of the best side hustles is delivering food from a local restaurant or fast-food chain. There are plenty of apps and websites out there which will allow you to do this such as DoorDash, Postmates, and GrubHub.
Write An eBook
If you have a knack for writing or enjoy sharing your knowledge about something, in particular, consider turning it into an eBook. There are plenty of online marketplaces where you can sell eBooks which include Amazon Kindle Direct Publishing (KDP), Barnes & Noble's Nook Press, and Apple iBookstore.