Different names

Hello everyone,

Hope you all had a good Shabbos with everything going on.

I saw this video where a kabbalistic Rabbi has a special Siddur for meditation, in it there are so many different names for G-d. I know different names are mentioned in the Torah at different places. Why are there different names for the Creator? Like what is the significance of different names? So does this serve the purpose of help focus during a meditation session? Also, could anyone please tell me what siddur he is using here?

I will ask this Rabbi as well. But, I would like to know your thoughts as well. Thanks.