Thank you for your comments. I know what are ISO 9001:2015 saying. But I would like to know if the standards can be changed a bit to make its requirements easier to apply?
If there is a part of the standard that really doesn't apply to your organization you can claim it as non-applicable (once referred to as "exclusions"). You can only claim non-applicability if you can justify it. One of the most common is design. If you are not involved with design you can claim it to be non-applicable and you need to explain why it doesn't apply.
For the most part, the standard is not prescriptive. That is, it lays out requirements, but doesn't tell you how to meet them. There is many ways to accomplish each of the requirements. So you have flexibility on figuring out how to meet requirements, often with very little modification to how you are doing it currently.
ISO 9001:2015 is a very basic standard. You should be able to figure out how to create a program to fit any company.