I lost my keys I don't have a extra set - 2000 Chevrolet Venture

From the 2004 owners manual...

"Replacement keys
If your keys are lost or stolen and you don’t have an extra coded key, you will need to have your vehicle towed to a dealership. The key codes need to be erased from your vehicle and new coded keys will need to be programmed. Replacing coded keys can be very costly. Store an extra programmed key away from the vehicle in a safe place to help prevent any inconveniences. Please visit an authorized dealer to purchase additional spare or replacement keys."

You need two functional administrative keys to program a third otherwise you will need the services of an automotive locksmith technician or have it hauled to a dealer.

Do you have any warning lights on the dash display? Without the electronic section to the key the vehicle is unlikely to start. The electronics turns off the immobiliser system so the vehicle will not recognise the key and not turn it off. Do you have the original security code for the vehicle? If you have this you can go to a automotive key specialist and they will be able to code new keys to your vehicle.
If you don't have the code you will have to go to a dealership and pay their silly prices for a set of keys.

You can't , anti-theft system an computers won't let you . Your best bet ,call a mobile lock smith an have a new key cut an programmed to the computers .

https://www.aa1car.com/library/troubleshoot_antitheft_system.htm

go to home depot and have a key made.

to reprogram new key first you need to use 2 factory program keys.place first factory key in the ignition first turn ignition on for 3 seconds. then turn off ignition then install second factory in the ignition on position for 10 seconds.when immobilizer warning lamp begins to flash a acoustic signal is emitted.within 60 seconds. switch ignition off and remove key.then insert new key and switch on for 10 seconds a acoustic signal is emitted and immobilizer warning lamp remain illuminated for 3 seconds indicating programming completed.if all fails dealership has to reprogram new keys.

there are many shops who can program your key and much more easier if you have a working fob key already.If not it is good to take your car to the shop with the new fob key and they will do it for you,I believe with less money than the dealer. Ask and try it.

you might have to get a locksmith to do it for you, that might be the cheapest way to do it .....hope this helps....cheers

You will sadly need to call a locksmith.
Please get an extra key made when you get the one made.
Put the extra one in a magnetic container and put that under the driver side on a flat surface.

Good luck
Rice

Take your car's VIN and other information to the local Jeep dealer.

They can make you a new set of keys.

They will require proof of ownership.

Depending on the dealer they may require you to have the vehicle towed to the dealership.

Even if the dealer is open Saturday, it may take until monday, since the key making folks usually on work normal hours.

Good Luck!

you will need to go back to the dealer to have it made or it wont start the car