See Release Notes

• Bug fixes for general core bugs in 3.10.x will end 8 November 2021 (12 months).
• Bug fixes for security issues in 3.10.x will end 9 May 2022 (18 months).
• PHP version: minimum PHP 7.2.0 Note: minimum PHP version has increased since Moodle 3.8. PHP 7.3.x and 7.4.x are supported too.

• Moodle 3.10 Database Schema (by Marcus Green)