1- For Eid prayer, can we pray alone or with our house member? Do we need minimum 40 people?
2- Do we need to have sermon after prayer?
3- First rakaat 5takbir 2nd rakaat 4 takbir, am I right?
4- Between the 5 and 4 takbir what to be recited?

1- Yes, you can pray it alone or with your family.
2- No.
3- Yes.
4- You can recite any dua between all takbeers.