Don't see why not, although you may not have all the features. The one that you want is the Home button which will get you to your smart TV features if yours is a smart TV. Should not be too hard to find a real remote for your TV model.
Sure, but a universal is not your plug&play replacement, it can take some effort to program them, and as ^he says, may not have all the buttons. A replacement remote, can often be found on eBay for not much.
To me a universal is not a replacement for a lost, is simply because I want to pool my individual remotes into 1, but I still want my original remotes to "teach" the universal what it cannot get otherwise.
If you get a Logitech Harmony remote those have at least as many functions as the original remote. There are sometimes codes that are not on the original remote, such as direct access to inputs, for custom installers to use for macros.
It will operate all your other gear as well. It's programmed from their online database so they have codes for just about anything. If they don't have the codes then you teach them into their database so the next person that needs them can download them.