It changes on a daily basis. If we don't qualify in the top two we would almost certainly be in a Group B play off where one of four progresses. At the moment we would be home against Northern Ireland in the first leg and if we won then home/away against Bosnia/Bulgaria/Israel/Hungary/Romania.
Hope it doesn't come to this but the best place I have found to keep up to date is here:
https://www.uefa.com/european-qualif...as-they-stand/