Overbite. Overbites don't go away on their own and the only way to correct them is to have Orthodontic treatment. Consult a local Orthodontist to find out what specific treatment will be necessary along with options, time frame and fees.
Usually yes. The only way to know for sure what the problem with your bite is, and what needs to be done to fix it is to see an orthodontist. Some problems can be corrected with clear retainers (Invisalign) , others require full braces. This can only be determined after the orthodontist does a complete evaluation.
Iceberg. If you have a bad overbite you are looking at the tip of the iceberg. Braces are the gold standard Orthodontic appliances, but there are alternatives. For the best answer to an Orthodontic question see a fully qualified Orthodontic Specialist for Initial (usually free) Exam and discussion of the treatment alternatives available to resolve your malocclusion.