Speaking as someone who is also relatively new to GSAP, I really recommend the courses @Carl runs at creativecodingclub.com. Having already gone through many, many hours of the content on there I can tell you there's some really good, clear information on the difference between from, to, and fromTo tweens as well as the "flicker" you mentioned and how to address it.
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Speaking as someone who is also relatively new to GSAP, I really recommend the courses @Carl runs at creativecodingclub.com. Having already gone through many, many hours of the content on there I can tell you there's some really good, clear information on the difference between from, to, and fromTo tweens as well as the "flicker" you mentioned and how to address it.