Android's support for 64 bit began with Android 5.0 in 2014. But today, Google's own Chrome for Android browser is still 32-bit.
The 64-bit is more efficient and secure than the 32-bit.
However, Google confirmed a few days ago that all devices using Android 10 or above will automatically upgrade to native 64 bit from chrome 85 version. Note that this is the stable version.
Slightly frustratingly, as of April, the coverage of Android 10 and above was only 8%, so fewer people would be able to enjoy 64 Chrome first.
As planned, chrome 85 will become official by the end of August. If you want to try something new, you can download Canary or dev version.
Moreover, according to a foreign tip during the dragon boat festival, starting next year's Android S( android 12) switch to a full 64-bit environment, the 32-bit program will not be running, just as apple launched iOS 11 2017.