Need help in Professional Military Staff

Am new to this game. I need soldiers and officers to create an defense unit but I don't have enough staffs. How do I recruit ?

Troops for weapons are automatically recruited from your labor pool.
Low Level Workers become soldiers, and Mid Level Managers become officers.

Build up your economy before you build your army, or it's going to screw up your country.

There are helpful reading materials in the Guide section of the forum. Whilst they may be a little old, the basic principles hod true and will guide you well.