Sentence structure is very complicated, you would not want to uses the same word in one sentence.
Yes. There is no English word that cannot end a sentence.
You just did. Sure! Here goes:<br>"Please tell your children to sit still!
The little girl bought a vanilla ice cream cone with a bright red cherry on top.
No it is not proper to end a sentence with the word "from" as it's considererd a prepostition. For example, the proper way to ask the question, "Where do you come from" is "from where do you come."...