Welcome TFW.
Example:
Dallas -6 vs Portland +6
if you like Dallas they must win by 7 or more for you to win
if you like Portland they must stay within 6 points of dallas for you to win
if it lands on 6 then you tie
-105 means you have to lay $105 to win $100 or $52.5 to win $50. if you lose, then you pay $105 or $52.50.
-110 means you have to lay $110 to win $100 or $55 to win $50. if you lose, then you pay $110 or $55.
Hope that helped. If not, keep asking and we will help.