Another computer question.

I know guys and I’m sorry to start another thread about this.. I have gone back and looked at a million old posts.. and they always just end up with people complaining about a brand and praising another.. I’m looking at garmin, wahoo, and hammerhead. (Not in that order) I will be using speed, cadence, and hr monitors, and turn by turn is a must. But what I want to know about is route planning. I know you can use Strava and what not, but can I just tell any of these I want to go for a 50 mile ride west of me with mild hills and it just makes a loop without a computer and minimal phone usage. I’m simple I just want to go.