1991 Toyota 4Runner transmission

I recently bought a 1991 4 Runner for a couple of hundred dollars. I knew it needed work but I could not pass up the deal. My engine purrs like a cat, but when I engage the gear selector lever from park to any other gear, the vehicle feels as if the transmission engaged but it does not move either forward or back. I changed the transmission fluid and filter already. I ask if you guys can assist me with this issue. I have the money to drop on a mechanic, but I would like the experience of fixing this vehicle myself.