Hi Jibel.
Which is exactly the ppa you’re trying to enable ?
Once again, as already said elsewhere, Budgie is Ubuntu so you may enable ppa.
If the ppa you target has no available packages for your version of ( whatever flavor of ) Ubuntu, it’s not Budgie ( or else ) 's fault.
As mentioned here « La version 1.10 [ de conky ] est présente dans les dépôts Universe sous Bionic Beaver (18.04) » and it’s still true in 19.10 or 20.04 see here also. Hence no ppa needed for conky, conky-all, conky-std or conky-cli.
Regarding conky-manager on https://launchpad.net/~teejee2008/+archive/ubuntu/ppa I can’t see there any package for 19.10 or 20.04, latest is 16.04. This project looks dead.
It seems it has been forked into conky-manager2 → https://github.com/zcot/conky-manager2
Only way to install this is by compiling it, following these instructions.