can v.s. could? deep usage?

[abcd1234]

hi, teachers.


How can i do this?
or
How could i do this?

which is the most appropriate between the two?
When do i use can and when do i use could?

thanks in advance.

[Tdol]

How can I do this? Asking directly for some help when you want to do something.
How could I do this? Asking for suggestions though you might not be going to do it, or are just thinking about it

[abcd1234]

thank you again tdol i guess you are one of the finest teacher in this world. :)

thanks.

[Tdol]

Probably not, but thanks anyway.

[englishstudent]

How can I do this? Asking directly for some help when you want to do something.
How could I do this? Asking for suggestions though you might not be going to do it, or are just thinking about it

tdol, could "How could I do this?" indicate a scenario where
I inadvertently did something and am uttering it? If yes, does
it fall under the "or are just thinking about it" part you wrote above?

Thanks

[Casiopea]

Here's what I would say,

EX: (uttering to oneself) "How could I do this?"
=> You are considering the kinds of potential options available to you.
=> questioning a non-past decision

EX: (uttering to oneself) "How can I do this?"
=> You know the options; it's a matter of choosing the right one.
=> questioning a non-past decision