Looking forward to...

I think this is a quite common mistake, but I don’t understand the difference between I’m looking forward to read the book and I’m looking forward to reading the book. Can anybody explain it? thanks

‘look forward to’ requires an -ing verb, so ‘I’m looking forward to read the book’ is reputedly an incorrect sentence.

The difference is that the second sentence is correct, and that’s more than you can say about the first one.

So, is it possible to say “I’m looking forward to hear from you”

Er… I just told you that it’s not, right in my previous message, didn’t I? Anyway, no, it would be incorrect. The correct sentence is ‘I’m looking forward to hearing from you’.