Betta Fish: i have no tank set up, is this a bad idea?

I saw this little guy in the pet store while getting supplies for my cat and I've never wanted a fish so bad in my life. He's absolutely gorgeous and I'm dying.

I have no tank, no supplies, and no real personal experience keeping a fish, is it a bad idea to take him home today? Obviously yes, but like, could I feasibly keep a $100 fish alive if I set up a tank this instant? I don't want to buy a tank and set it up, only to come back and he's gone.

Tldr: is it feasible to safely set up a tank for a betta fish and add them within a few hours?