how to install sims 4 onto usb flash drive?

It is possible to do that, have a look at this page:
http://gaming.stackexchange.com/questions/127822/is-it-possible-to-install-games-to-different-hard-drives

But I don't think an USB flashdrive is fast enought to play the game, but you can certainly try it.
I would suggest getting an external hard drive for your computer. 

(I myself use an external hard drive, which works perfectly. Origin usually thinks it needs to reinstall, but finds the game while doing so)

@Phantomlover1717 Not even high performance USB storage devices are sufficient for smooth loading of game data and you'll have to re-activate The Sims 4 on every system so there would be no reason to install it on a removable device regardless.

Hello, my names savannah you said get an external hard drive ive searched the interet on how to get one but it doesn't help me hoe do I get one?

Hi @savannahmaddie

it's a piece of hardware you will need to buy in a store.

It's usually just a hard drive you connect to your computer via USB

I use a flash drive to store my CC on (i moved the EA folder to my flash drive and deleted it of my laptop) but the game is still installed on my laptop so when i remove the flash drive the cc is not on there and i have no CC because it’s all on the flash drive and it works just fine for me. But i don’t recommend installing the game onto a flash drive along with the cc because your flash drive isn’t fast enough so your other option is to get a External Hard drive 1TB and you should be fine

Ok so I actually play from a flash drive and didn’t have any major issues. That is until I broke my flash drive. Is there any way to access my saved file.?