ask him for a ride

Hide his keys. Call a locksmith/car repair place and see if they can help out. Remind him that a car left un-started for months can result in a dead battery and other fun things. Start billing him for "leasing" your car. Get a specially bred key-sniffing weasel to find them. There are options!

If reasoning with him won't work an extreme option is going to a locksmith who deals with vehicles. if you prove ownership they'll be able to exchange the mechanism for your key and give you a new key. Then... there's reporting the theft to the police.

Soooo spending 15 mins in a car is worse than walking for god knows how long over ice and risking a bad fall or hypothermia? What happens if you sprain your ankle in the middle of nowhere? Your dad has shit reasoning op but good luck

Parent of the week award

Sounds like my dad. Recently, he refused to let me drive 15 minutes to work because it was foggy out. It wasn't even thick fog, but he was certain that it would be worse by the time I got off. It wasn't, and his paranoia made me pretty late for work. He wouldn't let me even get a driver's license until the end of last August because circumstances made it literally impossible for him and my mom to constantly chauffeur me anymore. I'm 22. And this is barely scratching the surface of how controlling he and my mom can be (but him especially). Your username leads me to believe that your dad has been doing shit like this for a long time. I don't know how old you are, but as soon as you can, just start doing as many adult milestones as possible without asking permission, because he likely won't change. That's what I had to do. My parents don't like it, but I'm not doing anything wrong and there's no reason why I shouldn't be doing these things at my age. In fact, if they had let me do certain things on time, I'd be a much more established adult by now, like most of my friends are. Parents like that are convinced that they need to protect you forever because you're their baby, and they will not listen to reason. They will likely never completely trust you. Your attempts to assert your independence will be met with resistance and attempts to put you in your place for a good part of your adult life, until they either get the message or kick off. They are coming from a place of love, but their actions are actually harming you, not helping. The fact that your dad hid your keys because he is worried about you is not sweet. It is controlling. He does not trust you to handle winter weather while driving, and even if he gives other excuses ("I trust you but not all the other drivers", "it's dangerous", etc.) he is still saying he doesn't trust you to deal with whatever happens on the road. He went behind your back instead of having a conversation about his fears, which shows that he doesn't respect you and his boundaries are skewed. And it's still dangerous to walk that far in that weather, let alone doing it all the time. Hopefully you can show him that his concerns are valid but his actions are unnecessary (as in, not having a screaming match, but doing things to SHOW him you're mature, and having a calm discussion). I'm sure you know this already, but don't be surprised if he still doesn't listen. I hope you get your keys back (or at least get another form of transportation), and I hope you're able to set boundaries with your dad. What he's doing isn't cool. Best of luck!

Just take his vehicle

"Okay dad, guess who gets to drive me 10 miles there, 10 miles back home, 10 miles back and then another 10 home! And gas is on you since this is your rule!"

Hide his keys, then! Better yet, just take his car, assuming he has one!

Just use a bus or uber or even a taxi...