Most easy ones are not very accurate..
Some can be found on line. I use the NKJV or New King James Version, or the NASB or New American Standard Version, but my 10 year old grand daughter can't read them well. Our grandson could but he is in advanced classes. Some people like the New International Version NIV but not the latest version of it. It was used by our Christian School because it is easier to read. The WEB or World English Bible also seems pretty good. It is not copyrighted so to be cheap. All of them have hard words for young readers. Some places to look online are studybible, BibleGateway, Biblestudytools, and bibleontheweb. You can try those out there before buying one.
We bought a book of Bible stories for the kids when they were younger, and both my husband and daughter in law read them when they were new believers because they had not been raised in church and didn't know the old testament stories or the things that Christ did. That and a New Testament are best to start with.