Learning GTM Engineering: Seeking Advice and Opportunities

Hi everyone I have worked as a marketing operation/automation manager in the last 6-7 years. I want to move a bit and learn GTM Engineer fundamentals. Unfortunately I don't have a job now, so I can't practice on tools except for the free account of Clay. Do you have an idea how can I learn? Or if you need someone to help (free of charge) in automation, enrichment, I would be very happy to talk to you