How can I compile the "wpad-mesh-openssl" and "mesh11sd" and packages
they're already available in the package repository ...
Sorry for my ignorance, but I'm just trying to learn. Can you explain a little more? they already exist in the package repository yes so I don't need to compile it? or if i want to compile how can i do that.
you need to build an openwrt system - https://openwrt.org/docs/guide-developer/toolchain/install-buildsystem ... also check the developer guide on this same "wiki"
select your device + packages (including the one you mentioned)
( and it's still not going to work on your plain Linux from OpenWrt - opkg install, if that's the intention )