According to this part of the main RPF website: https://www.raspberrypi.org/products/#buy-now-modal
(for the "Rest of the World", since Ghana not in the specific country list) the suggestions are "The Pi Hut", "Pimoroni", "Adafruit" and "Canakit". A check of their websites should, hopefully, tell you whether they can ship to you (and the shipping costs).
Still running Raspbian Jessie on some older Pi's (an A, B1, B2, B+, P2B, 3xP0, P0W) but Stretch on my 2xP3A+, P3B+, P3B, B+, A+ and a B2. See: https://www.cpmspectrepi.uk/raspberry_pi/raspiidx.htm