Laserbeam

I wondered if some one can help me with this problem which is I had a stoke at the end of August and have not driven since as my wife is not to keen on me driving at present.I have checked it out and there is apparently a test to see if you are fit to drive it is a SDSA.Can someone give me avice on it ie how you get test and is there a charge and what does the test consist of. Thank's