Liraglutide is probably better known as Victoza.
Glutides are GLP-1 agonists. Because they are quite a new class of medication they are still under patent so are not yet available as generics. This is why they are known by their brand name, inn this case Victoza, but it is also known as Saxenda in other parts of the world.
It also means they are still expensive, so are normally only prescribed when needed in combination with other medications, usually Metformin and a sulfonylurea, often after other medications have failed, and often only with severely overweight patients because they help with weight management. If not overweight and other medications have failed then insulin would usually be preferred. But the exact prescribing will vary by local policies and budgets.
GLP-1 agonists are also known as incretin mimetics as they simulate the effects of that hormone on the body. GLP-1 is an incretin, which are hormones released when you eat. It has the combined effect of stimulating the pancreas into releasing more insulin, the liver into reducing the release of glucogen, and suppressing appetite so you feel full. So essentially it increases the effect of the body's normal response.
In addition to appetite suppression, the medications also leads to some weight loss though the reason is unknown. But Metformin was first discovered a century ago and it still is not known exactly how that works either.
If you can get down to a normal weight than that should be one less injection as you should no longer need to take Victoza. And being a healthy weight should also reduce your insulin requirement too.