I have a set of points (X,Y,Z) across a river. Is there a way to present them as a cross section? I'm attaching a cross section I made in Excel: The X axis are the longtitude and the Y axis, the Z elevation data. I want to make such a cross section in QGIS.
In a first step, you should convert your point layer into a DEM raster: Creating raster or vector raster from DEM point file? or How to rasterize a vector map?
Then you can follow this advice: Drawing cross section in QGIS?