I advertised from linkedin and my websites. Upwork is bad. You would need to do some nearly free work for awhile to get some ratings and a 'rising talent' rating, to start to be considered for work.
Once you work for free for a few weeks you might start to get some traction but you'll quickly run out of "connects", that allow you to bid for proposals. Basically you have to pay upwork to apply to gigs, and then upwork takes a cut if you get the gig, and most the gigs posted want to pay offshore rates, eg 10 - $30/hr for AI work, or skilled software engineering.