Mouth kind of stinks, besides brushing my teeth, can i also brush my tongue?

Absolutely: Odor sources: gut, plaque (germs), pus (infection), cavities (rotting tooth). See your dentist to find the reason for yours. Until then: avoid foods that cause it (garlic, onions, certain spices); floss and brush your teeth (every night); use listerine (essential oils help), and cut out the extra sugars. Many odors come from the tongue, so consider using a tongue scraper to help clean the tongue.

Halitosis: Bad breath can be caused by many different factors, including sinus infections, periodontal problems, smoking, cavities, acid reflux, and your diet. Address all of these possibilities with your dentist and physician, and I'm confident that your problem will at least be minimized, and hopefully eradicated. Brush your tongue, but explore other possibilities.

Yes you can: However you should see your Dentist to determine the cause. Could be from food debris and bacteria collecting between your teeth, infected tonsils, an abscess, gum disease, throat infection. Infected sinuses, GERD, diabetes, from vitamins or supplements, etc. Please see your Dentist.