Welcome to the forum!
If you have installed new batteries into the remote and turned on the power button and the red light does not come on, and it does not operate the train, then the remote is probably defective.

There is no way to operate the train without the remote without modifying the locomotive.

If the set is under warranty, then you need to contact Lionel and request a repair or exchange of the faulty remote.

If the set is not under warranty, then you will need to purchase another remote specifically for that set. All LionChief remotes are different and not interchangeable, except between identical locomotive types.

Larry