В чем разница между assist и help ?Пожалуйста, приведите примеры.

Meaning is the same, but sometimes assist can sound a bit more formal than help.

Assist almost always means helping someone who is doing a task or job (they are doing it, you are helping them do it)

Whereas help can mean that also, but can also mean you are doing it for them.

Can you assist me to change the tire (I am going to change it, but asking for you to assist me to do it)

Can you help me change the tire (can mean the same as above, but also can mean you're asking them to do it for you)

If in doubt use help, won't be incorrect. It's also more common if using as noun

I could use or need some help
I could use or need an assist