>> Generally--
1) [That is right] = Saying that something is correct
"A triangle has three sides, right?" ---> "Yes, [that is right]"
2) [That's all right] = Along the lines of "it's okay," "it's all good," to express that something's not really a big deal
"Sorry for being late--my car broke down." ---> "Oh don't worry about it, [that's all right]"
^^Though more commonly used with [it's] instead of [that's]
3) [All right] = Usually said when agreeing to something, or to express that someone/something is fine
"Joey, you need to finish your homework before you can play." ---> "Oh [all right]"
"I just saw you bump into that pole, are you okay?" ---> "Yes, I'm [all right], thanks for asking"
NB: 2) and 3) are general/common use of the phrases. In cases depending on context, they can all literally be saying something is "correct," for example if talking about homework, all of the above can potentially mean "correct."
>> Not completely sure what it is you'd like to ask, but if you want to ask reception to receive/sign the package for you, you could say "My package has arrived, could you please help me receive (or sign for) it?" Or, if you're asking for them to bring it to you, "My package has arrived, could you please retrieve it for me (or "bring it to me")?" Hope this answers it, but please feel free to clarify if it isn't what you needed.
>> "I'm going to boil some water for my tea"
Hope it helps!