The batteries are listed directly under the drone's accessories on sale. Direct link:
DJI Intelligent Flight (drone battery, DJI Mini 2, DJI Mini SE)

My tip is to buy a good power bank for this money. You already have 3 batteries in this combo. So if one is empty, you could use the flight time of the next battery to recharge it. And honestly, even if it only lasts 20 minutes per battery because you don't use up the battery to 0%, you still have 1.5 - 2 hours of battery life with recharging. And the power bank costs about the same as a battery, but can also be used for other things. I was able to recharge very well the other day and after a short break I was ready to go again with 3 full batteries. At some point you will also have to recharge the remote control and mobile anyway.

The most important point about the drone itself: Make sure that you only download the original DJI app to your mobile. Even if you don't get it from the app store and have to temporarily deactivate security on your mobile. Most apps that are supposedly for DJI drones in the Google App Store only have the purpose of stealing from the uninformed (and are not from DJI).