You can get the SDK packages to build your app with Android 8.0 (API level 26) using the latest version of Android Studio (Android Studio 3.0+ is recommended).
Read moreHow do I find the minimum SDK version?
Go to: File > Project Structure , then under modules choose your module (that probably will be app , then under the tab flavors you can see minimum sdk and target sdk.
Read moreWhat minimum SDK version do you use for new app?
Generally, companies target a minimum version of KitKat, or SDK 19 , for new endeavors. For personal projects, we usually choose Lollipop, or SDK 21, as it brings a number of improvements to the table, such as improved build times.
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