where is since and from used are they same
You can refer to the answer given by your friend as it is very detailed and comprehensible. Here is some additional information:
'Since' as a preposition means continuously from or counting from.
It has been raining since last night;
She hasn't stopped crying since the time he left.
It also talks about a time between the past and the present. For instance,
There have been many changes since then;
He has been dealing with many issues since he has become the MLA.
From then until now or between then and now: They left town and haven't been here since.
Before now; ago: a name long since forgotten.
After some point in the past; at a subsequent time: My friend has since married and moved to California.
Continuously from: They have been friends since childhood.
Intermittently from: She's been skiing since childhood.
During the period subsequent to the time when: He hasn't been home since he graduated.
Continuously from the time when: They have been friends ever since they were in grade school.
Inasmuch as; because: Since you're not interested, I won't tell you about it.
from (frŭm, frŏm; frəm when unstressed)
Used to indicate a specified place or time as a starting point: walked home from the station; from six o'clock on. See Usage Note at escape, whence.
Used to indicate a specified point as the first of two limits: from grades four to six.
Used to indicate a source, cause, agent, or instrument: a note from the teacher; taking a book from the shelf.
Used to indicate separation, removal, or exclusion: keep someone from making a mistake; liberation from bondage.
Used to indicate differentiation: know right from wrong.
Because of: faint from hunger.