There are answer network, zero five network, elite network and so on. In fact, in addition to searching for answers on these websites, you can also download some search-related apps, such as homework help, Little Ape Search, Xuebao and so on.
Generally, these softwares or websites can find the answers you want, but more often, don't rely on these ready-made things, or you will learn nothing. More often, you should learn not to be shy about asking questions, so that what you learn and ask is your own.