Hi Isabella, I can help you with both programming and SEO stuff. My estimation is very approximate because it depends on the platform your website is currently running on.
Regarding the SEO part - I can send you an example of keyword research which includes keyword ideas with approximate volume and difficulty score and some content ideas.
Please let me know if your project is still relevant, I'll senf you a sample PDF.
And also please give a bit more details regariding your website - is it a store? What platform are you currently using?