Whether you are disabled depends on whether you are able to return to any of your past work — that is, work that you performed in the 15 years prior to becoming unable to work — and whether there is any other work that exists in significant numbers that you can do.
SSA is going to decide what your “residual functional capacity” is. In plain English, that means that they are going to decide the maximum that you can do with your specific limitations. Your residual functional capacity determination is based on a review of your medical records.
After they decide what you can do, they will compare that with the demands and requirements of your past work. That means that they need good, realistic information from you about the specific demands of your past work. They will not necessarily be checking with your employer to make sure that your jobs were as you described.
Once SSA has determined that you are unable to return to your past work with your residual functional capacity, they will turn to whether you are able to do any job whatsoever and whether you have any transferrable skills from your past work that you could apply to other jobs.
Whether you have transferrable skills depends not only on your past work but also your medical conditions. For example, you may have had highly skilled past work but suffered a brain injury that left you unable to remember names, places, and instructions. In that situation, you probably don’t have transferrable skills.