or go to You tube and type in Basic maths into the search box
but if the subject ( you know not you but your fren' ) needs really basic maths then it may be better to attend a course ( that is be taught )
and there are zillions of these - adult numeracy as it ( the govt thinks ) isso impt.
Far better to find a course at a local collage where you will get individual attention from the tutor. That way you will get a course tailored to your personal circumstances.
Go to Youtube and search hegartymaths. You'll find tutorial videos that might help you with what you need. The chap who set it up was recently shortlisted for best teacher in the world (or similar)