I've been doing a lot of tweaking on my phone lately. One of the biggest tweaks was witching from Samsung Messages app to the Google Messages app. Google Messages is way better to me. A lot more options. A faster UI. I also switched my keyboard from Samsung to Google, and I've really enjoyed the change in how my Note 20 Ultra 5g operates. It may not be for everyone, but try it and see how far you get with it. You'll thank me later.
So I mainly downloaded it because it showed it had the option to give reactions to messages but it's not happening. Then I read something about the other user has to have something turned on. Outside of that, no real benefit that I see
Yes. Just look at your messages apps. You should already have Google messages. If not, you can always download. You just have to make it your default app. Same with Google keyboard!