This is my first time I saw a real lacewing in my garden before only I have seen pictures on the net. I do not know how to take care of it and how long it'd remain to my garden.
Any advice will be appreciated.
You don't take care of it. Keep pesticides out of the garden. The adult females will lay eggs and the larvae are aggressively predaceous.
Rhizo_1, thank you for the advice.
as long as you don't spray any bug killers and there are food bugs for them to eat they will stay and be just fine.
Scropman1, thank you for the advice. I do not use any bug killers I am not good at with them.
I enjoy my garden now, I got so many beneficial insects, such as lacewing larvae, different kinds of ladybugs (color and size), predator mites and harvestman spiders :-). I did not plan very well for my garden and this is also my first time growing vegetables/plants everything goes so smoothly except the tomatoes. Tomatoes are drooping leaves because I am growing it in growing bags and the water dries so fast, at lease I have to water twice a day still they are doing very well. Before I hate gardening now I love it and I would like to get more space for my garden, this hobby is really addictive and relaxing.