Hi guys, welcome to our community.  I am going to try to explain some of the questions that you asked above.

By gifts I assume that you mean rewards.  To get free rewards without money, you have to play the events that might be posted in your game.  The events will be posted in your trophy box (see picture below).  It can be build-a-bot where you have to complete each level on the first try and then you will get a reward that is placed on your next level when you open it.  It could be an event such as Dexter's Space Race where you have to collect color bombs in a certain time frame.  The top 3 that collect the most will get rewards.  They vary from player to player because the studio randomly picks players for an event.  You might not get what your friend has but you will get something else.  After a certain amount of time the studio can change who gets what.

On the Booster Wheel you can spin it once every 24 hours for a free boosters.  Those will be saved in your backpack (see the picture above - top picture).  Not all rewards get saved in the backpack.  Sometimes you will get timed boosters which means that you might get a booster for free to use for 10 minutes.  That will be used when playing your next level.   The timed rewards don't go into the backpack.

Also there is the daily bonus. Every day when you open up the game the treat calendar should pop up and give you a reward for that day.

To get extra lives you have to request them from friends but they are not friends that you make in this community.  If you play through Facebook then you have to join a group for that game and ask the members to add you as a friend.  Then when you need lives you would click on the Heart located on the left side and from there you can request them.  If you are playing through King on king.com you are out of luck because there are a few glitches and the lives is one of them.  If you play the game on mobile you can also get friends to give you lives if you login with your King account.  Those friends are randomly chosen for you but same thing, you would click to ask or receive lives.

See the first question that will explain how to get these rewards.  There is also the Sugar Drop challenge that you can play for free rewards.  Some of the levels are specific for the sugar drop challenge.  You will see which levels they are by the letter "C" that will show up on the level.  When playing those levels you will see the "C" wrapped around some of the candies.  You have to match it with 2 others for a match 3 and they get added to your level.  When you meet certain numbers you will get a reward.  When you reach 180 you will get your final reward and then have to wait 8 hours before it starts again.  If you are looking at the map and don't see the "C" shown on the level number that means you opened the game before the 8 hours finished.  Sometimes you can get a free gold bar just like you see in this picture.

The only way that you can get extra coins (gold bars) is if you play the Sugar Drop challenge or purchase them from the store.   You can buy just gold bars or a package deal with some gold and some boosters.  Be careful with the timed boosters because the clock will start ticking once you finish paying for the package and you cannot stop it if you walk away from the game.  Once it starts ticking like a clock it goes to the end and then it's done.

The competitions are usually posted here.  Each game is listed separately so you would want to click on the game(s) that you play and it will show you the current and finished contests for that game.

I think I might have covered it all but if not, please let me know.  @Spinnifix you might want to hold on to this link just in case you have players ask these questions in the future.  You could always direct them back here with these pictures.