Let’s see if I can give at least something understandable. To start with, definitely not past tence.

If you ask “would you like coffee?” you’re asking in the present if coffee is something the person wants to drink now. If you ask “would you go to the store?” you are asking if the person doesn’t mind going to the store.

Could is similar but is slightly different, is to ask if the person can do something.

Could you take out the trash ? - are you able to take out the trash?

Would you take out the trash? - do you mind taking out the trash?

Not sure this helps, but in project management there’s this think called the MoSCoW scale to define how important a requirement is, it looks like:

Must (you have to do it)

Should (very important but not as important)

Could (not important but if you can you should do it)

Would (would like to have, this is definitely not important but if you have enough time it’d be great)

Always liked this because it helps people see to some extent where money is going.

I know the UK and Portugal do this as well. It was especially interesting in the UK during the Brexit years because you could see a tiny piece of that pie chart with EU contributions, almost saying “this is how little of our money is going to Europe”, didn’t do any good in the end but hey, still great info to have that all detailed