Is there any oral insulin medication available for diabetes (type 1) patients or insulin injection is the only option?

Injection only: Insulin is by injection only. There are no oral preparations of insulin for type 1 Diabetes.

Type 1 needs insulin: Type 1 diabetes occurs because the insulin-producing cells of the pancreas are damaged. The pancreas makes little or no insulin, so sugar cannot enter the body's cells for use as energy. Insulin injections are needed throughout lifetime. In Type 2 diabetes, the pancreas is still making insulin but it may be insufficient or ineffective.