I would honestly expect extraterrestrials to resemble Earth animals overall. We evolved into the bodies we’ve got now because they’re pretty convenient for our environment.
Humans have two legs because it allows for a roomier birth canal, to accommodate those big bloated brainy heads. And we have a digestive tract to accommodate different kinds of meat and plants because we need as much nourishment as possible for those brains.
Those considerations would still exist on other planets, so I wouldn’t expect the life forms to be too different. Boring, but reasonable.