Remember that you are taking a very big security risk if you stay on outdated software.
An incalculable risk.
You will no longer receive any security updates.
Not a very big risk to be fair. Very few (vanishingly few?) recent security vulnerabilities in recent versions of Android that pose a serious, realistic, readily exploitable threat to ordinary phone users in normal use. When talking about ‘risk’ in the context of phone operating systems, it’s worth keeping a realistic sense of proportion