How to handle research advisor meeting stress
It sounds like you're a new graduate student, and that you clearly care about performing well in your program. You stumbled, and you've accepted responsibility and looking for ways to correct the problem. That's great, and suggests that you will end up doing very well in your program. As a master's student, you're not expected to be able to work completely independently, and your professors will likely be happy to help you navigate your program (they certainly should). The key is to ask for help early and often.
I would consider scheduling an appointment with my adviser, telling them exactly what you've said here, and asking them for advice on how to prepare for meetings, and perhaps even advice on how to structure your independent learning so that you're learning the specific techniques/concepts that want you to know at each stage. Every adviser is different, so the best advice you can get will come directly from them. It may be intimidating to ask for help, but it is completely appropriate at this stage in your graduate education.