Is it true for both solar and stellar paths? The nearer to the poles, the more horizontal the paths they are.?
True most of the time, but where the Sun rises and sets along the horizon MOVES.
paths of what?
If the OBSERVER is at the pole, then the daily path (star or Sun or anything else) is horizontal = stays at the same altitude all the time. If the observer is at the equator, then the daily path is vertical (objects rise with their paths making a 90-degree angle with the local horizon). If the star is at the pole (the Pole star, Polaris) then it has no path. The rest of the celestial sphere appears to turn around it (Polaris makes a tiny circle around the real celestial pole, because it is not exactly at the pole) Anything in between gets... something in between. The closer you are to the pole, the "flatter" the daily path will appear. --- In practice, for an observer AT THE POLE, the path of the Sun is a very slow spiral that you might not notice over a 24-hour period. It would take 3 months for the Sun to go from being on a path at the horizon (mid-March), to reaching its maximum altitude of almost 24 degrees on June 21. It would be a boring observation program (unless you observe for another purpose). The fastest rate of "climb" would be 0.4 degrees per day (almost the apparent size of the Sun's disk) in the second half of March. Combine that with the closeness of the horizon (giving you a line of reference) and it could be noticed from "day-to-day" around that time of the year. However, soon after that (say end of April), you might not notice the daily change unless you could actually measure the height above the horizon (with a sextant, for example). The Moon would have much faster rates. From being on the horizon to reaching its full altitude (could be almost 29 degrees on certain months) takes only two weeks. Careful observing could even make the climb visible from hour-to-hour. Venus would have a rate somewhat close to that of the Sun. Mercury might have a higher rate (it could be circumpolar during local twilight, making it easier to see. Everything else would appear to have flat paths. Except Polaris, which would seem to just sit there, at the zenith (directly above you). But that is not useful information since, for people like you and I, we can only go there during the "summer" (while the Sun is up) and only by using up a lot of money.