A few bugs suddenly flew into the house, a bit like bees, and very big. What are they?

According to your description, these bugs are probably wasps. The wasp is a common insect and usually flies indoors in spring. They may fly into your home because of the weather change and looking for food or habitat.

Wasps don't usually attack humans, but they have the instinct to protect their nests. If they feel threatened, they may attack humans or animals. Therefore, if wasps are found harassing your home, you'd better take some measures to drive them out of the house.

Here are some ways to get rid of wasps:

1. Spray: You can use some natural spray, such as lavender or lemon juice, to spray on wasps and drive them out of the house.

2. Use wasp bags: You can buy some wasp bags and hang them in places that are easy to disturb, and the wasps will be attracted to the bags.

3. Remove the nearby flowers: Remove the flowers near your home and reduce the activities of nearby wasps.

If wasps continue to harass or attack humans or animals, it is recommended to seek the help of professional pest control companies.