If you think that you home needs a major adaptation like a stair lift, you'll need to get in touch with your local council to request an occupational therapist assessment. They will then visit you and assess your needs.
Depending on the outcome of your assessment, the council may fund your adaptation. We're not able to install a stair lift or any other major adaptations for you.
You can learn more about what to do and who to get in touch with here.