He plays up front, receiving passes from midfield, wing, defence. He's a striker, even if FPL and your computer games tell you different.
He is a forward, a winger to be precise, not a striker. FPL classifies every winger as a midfielder and while it is not technically correct, it doesn't make Salah a striker.
A winger... Plays on the wing. Clues in the name. Salah runs onto through balls and gets on the end of crosses. You get very few true wingers these days as the wing backs take up most of the traditional wingers duties in most systems played in the Prem.
You don't understand football, do you? Please watch a few basic videos and learn about positioning before making yourself look like a fool.