droid 4 xt894 version 4.1.2 looking for safe root and android 4.4 or higher upgrade

Yes I am very old school and smart phone newbie not wanting to give up on my physical keyboard yet. I'm running android version 4.1.2 and would like to root my droid 4 to update the android version to the newest one my droid 4 can handle. New to all of this so just need help or advice on how to safely do this using a pc running windows 10. Most apps I run require os version 4.4 or higher. I googled and seen many how to's but don't want to download anything unsafe to my pc. Need a trusted site
Any help would be appreciated thanks,
tam198

 

Thanks, I know its an old droid version but actually new condition, I seem to suffer from fat finger and would prefer to use this one (actually have 2 droid 4) for awhile longer until I can master the no physical keyboard part. Hopefully someone will know or at least point me in the right direction. thanks again for you time.