In my project I want to analyse the landuse around some points within a certain radius. So I created a buffer around my points but I have no idea how QGIS could probably tell me what different landuses are laying inside of the buffers (like 2 km² forest, 3 km² residential etc.). I have already loaded a vector layer which shows the different landuses in the whole area in general on the map.
I would use the "Clip" tool to "cookie cut" the land use layer within the buffer zones you already created. the input dataset will be land use and the clip data set will be the buffers.
From there you will have a new layer of land use data only within the buffer zones. You can repeat this process for additional buffer (radius) values or use a Mulit-Ring Buffer Analysis and then Intersect to Land Use.