- How I can or can I?
- Is it for I can or so I can?
- Can I or may I Which is correct?
- Shall I or can I Which is correct?
How I can or can I?
"how i can": Can you show me how I can handle this camera? So, the correct form will be how I can because your question is started with could, so no need to form the second question with how can I in the same sentence.
Is it for I can or so I can?
The only difference between the two verbs is that one is more polite than the other. In informal contexts it's perfectly acceptable to use can; in formal situations it would be better to use may. Can means you're able to do something.
Can I or may I Which is correct?
May is the more formal word, and if you are at all concerned about being tut-tutted, a safe choice. Can is now the verb of choice for ability, and both can and may are still used in the "possibility" sense. You may use can if you wish, and you can use may if it makes you feel better.
Shall I or can I Which is correct?
Shall is always in future tense and can is always in present tense.