In TC 6 x86 the extensions are called:
apache2-mod-php5.tcz
apache2.4.tcz
Not:
apache2.4-mod-php5.tcz
Review the info files, you need to decide what you need.
Assuming you have graphic environment, open Apps > Clout/Remote > Browse, in Search enter Apache, select apache2-mod-php5.tcz or whatever and at the bottom click OnBoot Go or OnDemand Go. Don't recall if the extension is automatically loaded. If not select Apps > Load App Locally > select your new Apache.
Edit: Just noticed your first post mention. What architecture, are you using an Arm device?