Note: when you root your phone, your warranty will be gone. But you can get it back by unrooting your device. Root your device at your own risk, if you don’t know anything about rooting or what will you acquire by rooting; I will suggest don’t do it.
1.Download KingRoot and install it.
2. If you see a warning box then you require to check this option, Settings > Security>Unknown sources.
3.You will see the KingRoot icon in your App Drawer. Tap on the app icon to open it.
4. Once the app is lunched, click on try it, It will try to analyze your device to find suitable root process. You must turn your data connection on during this process.
5. Tap on “START ROOT” button that shown at the bottom of the screen.
6. Wait for a few seconds as Kingroot tries to root your phone.
7. Once your phone is rooted, you will see a Root successful message.
8. Confirm your A2010 or A2020 is rooted by using any app that want root privilege to perform it’s work. (E.g. flashify, L speed, Titanium backup etc.)
I have use screenshots of KingRoot on Lenovo A2010 but it will work the same on Lenovo A2020.