Welcome to Android Central! I can't really compare battery life, but I can tell you that I have the Lenovo Tab M9, and have been quite satisfied with it. Performance is significantly better than the M8 (which I previously had), and I appreciate the stereo speakers. The M8 only has a mono speaker, although it does have the advantage of offering a 1080p display (if you get the M8 FHD version), while the M9 only comes in a 720p version. I use my M9 primarily for media consumption (reading on Kindle, watching streaming videos on various platforms) and browsing, and I never feel that the battery runs down too quickly.
I would stay away from the Galaxy Tab A7 lite. I had that for a while, and although the specs look good on paper, I noticed that it got progressively more sluggish over the span of a year, to the point that it was almost unusable (or at least very unpleasant to use). I ended up trading that in for the Lenovo Tab M9.
I don't have any direct experience with Amazon tablets, but just remember that they don't come with the Play Store -- you're stuck with Amazon's fairly awful App store, with a much more limited app selection, many of which don't get updated as much as the ones on the Play Store. There are ways to get the Play Store installed -- you can search on the web for that -- but if you don't want the hassle, avoid Amazon tablets.