Online play is not much different from table play. Both sides have the same pieces, dice, and game board. To play online a game site must be located. However, that is easy to find. Most sites are free to play on but registration is required. Depending on the site, you can play against a computer or other opponents. To play online, there will be a place to click for the dice roll during your turn. Once the dice are rolled, you can move the pieces you would like, just as you would for a regular backgammon game. And the game is won the same way; get all your pieces off the board before your opponent.
The nice thing about playing online is you dont have to play. You can just watch and learn if you want. This might be the best thing to do if you are just starting out. But when you do want to play you will be able to join in easily. And most sites have a tracking system so you know how well you are doing compared to other players.
Some sites are played for money. While it can be fun, it can also be dangerous if you are not careful. If you want to go this route, start out slow and only play for modest fees and winnings. Also remember that tournaments are played for...