Unfortunately this problem is not specific to ancient Egyptian and automatic translation will generally not really be anywhere near understandable. Ancient Egyptian also has the problem of being a language for which no automatic translation software exists, as far as I'm aware (translating things into Ancient Egyptian is not really a common problem).
If you want a semidecent translation of English into Ancient Egyptian, you can try several things :
- Pick up an Egyptian textbook and try to grasp the basic grammar and try to construct a sentence from it. "Middle Egyptian" by James Allen is the most common one, I believe. A good Egyptian dictionary might also be useful.
- Check Egyptian texts for any similar sentences, if it exists. This is a pretty good resource of Egyptian texts, although the transliteration isn't always provided but you can always try to find one via the references given.
- Ask someone knowledgeable in Egyptology to give you a hand for it.
Of note, the British Museum produced an Ancient Egyptian translation of Peter Rabbit
The notes about it are quite useful to see some of the general difficulties involved into translating modern day texts into Egyptian, such as the lack of words for a variety of objects (umbrellas, wheelbarrows), plants and animals which did not exist in Egypt at the time, as well as words that are just unknown.
Also you should decide what era of Ancient Egypt you use. Written Egyptian was mostly stable through its rather long life, but it went through several eras still with different grammars. The main stages are Old Egyptian, Middle Egyptian, Late Egyptian, Demotic and Coptic.
If it is supposed to be spoken Egyptian, also remember that for the most part, we do not know what Egyptian sounded like. Egyptian did not write down most vowels and sounds have changed through its history as well as with regions. Some words were also not actually written down and were supposed to be grasped from context (for instance it is suspected that articles, "pa" and "ta", were used in spoken language but were not written down until demotic).
As for a language sounding like Egyptian, its closest relative today is Coptic, which unfortunately is almost dead. Coptic is nowadays only used as a liturgical language for the Coptic church, and as such may not have a very extensive literature for translating into English, but you can always give it a look. The closest living relatives of Egyptian are the Afro-Asiatic languages (such as Hebrew and Arabic), but they are separated by almost 5000 years.