I'm definitely not the best person suited for this but I'll try my best to answer both your questions:
EMDR is a structured, evidence-based psychotherapy designed to alleviate distress from traumatic memories, in simpler words is a trauma therapy, it helps you to reprocess trauma through bilateral stimulation such as guided eye movements sounds, or taps. It's very useful for ptsd, anxiety and phobias.
In my personal case I suffer from anxiety and ptsd, it was a great course of action but I highly recommend to do it only after you've done a hell lot of therapy to develope tools that can help you deal with high stress situations because EMDR makes you face things you are not even aware of, so as a patient you have to be really ready to face what's coming. If you go to therapy regularly I suggest you talk it through with your therapist first if it's the right path for you, there are many other options out there to heal yourself :)
If you have any other questions or you wanna talk to someone about it feel free to dm me!

I only came here because I did EMDR therapy lol