What resources did you use when learning or reviewing tefillah? I don’t know if it will work for others, but it has helped me to have had a strong intellectual treatment of the purpose, structure, and order of our prayers, and how they are so central a statement of Jewish “theology”. (I put it in quotes because it is really something that Christians put a lot of emphasis on and I don’t think that is exactly comparable to anything in Judaism.)
Three resources that have been particularly helpful to me that I can recommend:
‘??? ? by Rabbi Moshe Chaim Luzzato. There is an English-Hebrew version with a translation by Rabbi Aryeh Kaplan z’tz’l published by Feldheim. I went through multiple detailed passes through it with a rabbi. The last section is about tefillah but it builds on everything earlier in the sefer.
Rabbi Lord Jonathan Sacks’ commentary in the recently published Koren Hebrew/English siddur.
The commentary by Rav Soloveitchik z’tz’l in recently published machzorim for the Yomim Noraim.
Not only have these enhanced my intellectual understanding of what the prayers are about, and to Whom I am addressing my prayers, it helps me with I’m in one of those minyans where it seems that everyone is just going through the motions at best. I can often shut them out, concentrate on the words, and talk to God rather than to the Shul Talkers. They also increased my admiration of our great sages who commissioned these brilliant prayers.
I hope this might help someone.
All the best!
Charlie