Need help for setting camera.

I’ve lost all patience to find out out what’s wrong…
First I can’t set up a camera properly, it’s the most annoying part. I select a nice view from render view and when I press 0, the camera focus some else direction…and it’s way to hard to point the camera where I’m actually seeing. And after re-pressing 0, I get upside down object. And if even I set a camera badly anhyhow, it doesnt want to move as i make it . And then when i zoom out, (after this camera mess), my object goes inside the background…like there is some invisible wall which is taking the object inside. so i always have to keep it very closely zoomed and thus can’t point anything. I made few models before, but i didnt move the camera, so there was no problem. but for my last model, I must move the camera. I made a nice model , I only can’t render it for the camera Oh the best part - after all this, if i managed to point the camera somehow, it give a bird eye view…i mean the square plane looks like a round plane.

Numpad 0 changes the view to look through the active camera.
Ctrl+Alt+numpad 0 aligns the active camera to the current view in the 3d view window (look in the View / Align View menu)
In the properties panel (N) there is also the option to Lock the Camerw to the View. When in camera view mode you can then move the scene aroundwhilst always looking through the camera.

Note in the Porperties panel and camera settings there are clip start/and end values to determine if an object is visible given the distance to that object.

I tried the ctrl+alt+0 already, but didn’t work in that particular project… To check everything is alright or not, I started a brand new project and the camera movement I could control easily by locking it to view and then rotating the scene. But something must be wrong in the project I’m doing…I just can’t figure out what… and associated problem remains…which I described before…
1.the scene gets upside down after setting camera
2.the object and the plane gets inside the background (you can see in the screenshots)
3.square plane looks like round one.