First off, if you don't have a point layer already built with the geographic coordinates of your evaluation points, build it from a csv list. You then need to add a field in that layer with the variable that will serve as the radius value you need if it wasn't already in your csv list.
You can achieve what you want with two tools accessible from the vector menu. The first thing is to use Buffer, found in geoprocessing tools. In the distance parameters, you can use a data defined override and provide a field to control the radius. See here.
If you need only certain points counted according to their attributes, use select features by value from the main toolbar. You get a list of each field where you can type the value you are looking to select with. On the right, there is a drop down menu where you can set your query operator (equal to, contains, etc.). After executing the selection, run the count points in polygon tool, found in the analysis tools menu within the vector menu. Set your polygon and points layers, make sure you tick the Selected features only checkbox and then run the tool. It will output a new polygon layer with an additional field named NUMPOINTS (by default - you can rename the field in the tool) where the point count will be located. See here.
You'll need to repeat the process for each of your evaluated variables (once if you are only looking for african or european as your values). Then you can merge the attribute fields into one polygon layer.