Sanny wrote:

When I see sky I only see small stars twinkling at night.

http://www.mazepath.com/uncleal/sunshine.jpg
Eat more mica

Now When I see sky with a large telescope I will again see many stars.

How do I know whether a twinkling Object is a Star from our Galxy or
it is some other Galaxy.

1) You look up the sky coordinates in a catalogue or use software.
2) You look at the (resolved) image. Stars don't have structure or
extent.

How do scientist see the very far away Galaxies and see Billions of
Stars in it.

Bifocals.

Can they really see each star in the Galaxy and how do they count that
there are 100 Billion stars in that galaxy.
[snip rest of crap]

103,475,223,482 stars. Oops, supernova! 103,475,223,481 stars.

--
Uncle Al
http://www.mazepath.com/uncleal/
(Toxic URL! Unsafe for children and most mammals)
http://www.mazepath.com/uncleal/lajos.htm#a2