The dilemma is that although there are recommendations like fast.ai to get your hands dirty quickly into ML/DL, none of the good AI researchers and practitioners got there via these quick tutorials. They got there via rigorous linear algebra, traditional ML, statistics and related computer science knowledge.
I would say try fast.ai for a quick taste of what ML/DL is like, and then go back to linear algebra, deep learning and stats courses from top schools while picking a personal project goal to achieve (e.g. reproducing a popular CVPR/ICML paper results or building your own XXX) Once you go through a full lifecycle of building something from scratch, you will have a much better understanding about where you are and wanna go from there.
I would say try fast.ai for a quick taste of what ML/DL is like, and then go back to linear algebra, deep learning and stats courses from top schools while picking a personal project goal to achieve (e.g. reproducing a popular CVPR/ICML paper results or building your own XXX) Once you go through a full lifecycle of building something from scratch, you will have a much better understanding about where you are and wanna go from there.