How can i get a flat tummy by summer?

I’m 5’1 and I weigh 94 pounds. I know I’m not fat but I’ve notice that my stomach isnt at all toned. I dont have any fancy ab machines. Haha!

What do you think I can do to have toned waist? Do you guys have any cardio/ab workout plans I can possibly try?

Btw, my friends and I are planning to start exercising but we dont know where to begin ! help?
thanks!