If you know Ernest:
If you know and love Ernest you will get more of his silly/stupid humor in Ernest in the Army. If you enjoy other Ernest movies you will likely enjoy this as well, though it has a bit less of his typical shenanigans like dressing up. I recently was looking up Ernest things and apparently, there is an order to watch the movies in because they have their own over-arching story of him growing up. This is the last one where he is basically an adult now. While this is the last Ernest movie I'm not sure if there would have been more had he not died when he did.
If you aren't familiar with Ernest:
The character of Ernest initially appeared in commercials for things like ice cream and soda and they were all stupid/silly funny. Then they made several movies where the Ernest character gets into a variety of situations and he stumbles his way through them in silly/stupid ways that typically involve him getting hurt at some point and everything working out in the end. Each movie has a general theme like teamwork, never giving up, don't cheat, etc.
This movie starts with Ernest hanging out with his friend in the Army. Ernest wants to drive Army trucks so he enlists in the Reserves just in time to be sent on a UN mission to stop a terrorist from launching a missile. It has a lot of comedy and it's fun and enjoyable for the family. I grew up watching Ernest and while I still enjoy them as an adult I admit they aren't quite as good as when I was a kid, but they are still decent if you enjoy the silly/stupid funny type movies. It's not great, and I think they could have done it better, but still very enjoyable. I don't know anyone else who can turn a pancake into a weapon.