You can add production items with the Add command. They're added to whatever's in the selected square. Add Orbital Scanner
You can add technology like this AddTech The Humans Advanced Psi Shield
There isn't a command to add population.
Use the category and selector drops on the right to find out what things are available, and to avoid having to type out the name. Use the recent box to reuse recent commands (these are saved from game to game).
Figured out the add tech before seeing this, found the colonize planet too. Haven't see anything to make a poor planet into a rich planet though. Looks like the change planet type does not work. Thanks.