About Touch Based movement and some other minors doubts.

Hi there! I have been developing little "Grid/Tile-Movement Base 2Dgame" for Android .. and i am completely lost :/ I have the game working fine on PC but i don't have any idea of how to make it work based on Touch-Controls. I was thinking on creating Raycast based on the touch position ... like a "Touch-To-Move" game ... but i am with no Internet connection so i cannot do In-Depth research!! :'/ I already checked the entire Unity Manual and Scripting API (Offline files inside of Unity installation folder) but the specic topics that i need are not usable for a novice like me. So i wanted to see if you can share with me a good Documentation or Video around the web that may help me with my problem! -. If not i would really appreciate if you help me with the following logic: --What's the best way to make a "RayCast" based on the "Mouse click point"? i was trying to move my charater based on the position of the mouse click but i haven't been able to get it to work.