
You may have been exposed to burn pits, Agent Orange, chemicals or other hazards. VA pays for a diagnosed condition, not for the exposure itself.
VA says you must have a current illness or injury (a condition) that affects your mind or body, and you must have served on active duty, active duty for training, or inactive duty training. The condition also has to be tied to service: it happened during service, a condition that existed before service got worse because of service, or it is service-related and showed up after discharge. VA then assigns a rating.
For some conditions VA presumes the exposure. VA says: "If you have a presumptive condition, you don't need to prove that your service caused the condition. You only need to meet the service requirements for the presumption." You still need a diagnosed illness or health condition. For a condition that is not on the presumptive list, you must submit evidence that connects it to your service.
VA expresses a rating as a percentage, and VA's compensation rate tables list ratings of 10%, 20%, 30% and so on up to 100%. Your monthly payment depends on your rating and your dependents.
The VA toxic exposure screening is a health care step, not a claim. Filing a claim is separate. See Burn Pit Registry and Toxic Exposure Screening.
Official pages that do the thing:
Free help: VA says services from an accredited VSO representative on VA benefit claims are always free. Find an accredited representative or VSO.