How do you see the whole of milky way if we are in it?
Obviously you'll not see it all. If you're lucky enough to live someplace where it's visible, be happy and enjoy. I understand, from the local observatory guy, that about 80% of children in the US have never seen it.
Here's a similar thread from September. It may answer some of your questions (and give you a laugh or two).
The best way to "see" our home galaxy is to dig up images of barred spiral galaxies and use your imagination. We are reasonably sure that the MW is a barred spiral, and they are fairly common, so images are not hard to find. I live in central Maine. In the summer I get to see the "fat" bright part of the MW, toward Saggitarius, and in the winter I get to look at the next arm out and see Orion, etc. Our view of the MW is necessarily constrained by the Earth's location in it, and by our location on the Earth. I have never seen the Southern Cross, nor the Magellanic Clouds.
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