You cannot simply move excel code over to Access but I'm not understanding why you would want to. If Access is a hammer, Excel is a wrench. Being proficient in spreadsheets and approaching db design with that mindset is actually a bad thing. Your task might not be too onerous for someone with Access experience but if you are a novice who has done no prior research or learning you will likely be here asking for help often. You will do all sorts of things that you shouldn't. Unfortunately the advice given is often to fix the design.
Your code rate data likely can be imported into a properly designed table in one of a few ways. What's best will depend on how you have laid that out in a sheet. If it resembles a normalized db table, TransferSpreadsheet function may be all that you need. If it's not, then queries, perhaps on the sheet, linked or imported as a staging table.
Maybe what you should do is some research - assuming you're the one who would build this. Access is probably a better tool for your needs, but not if you build a bad too with it. Suggest you start with db normalization. I have a bunch of links for beginners if you'd like to review various subjects.
The more we hear silence, the more we begin to think about our value in this universe.
Paraphrase of Professor Brian Cox.