The in-practice ”How”.
A project is ”a piece of planned work or an activity which is done over a period of time and intended to achieve a particular purpose”. (Cambridge dictionary)
A formalised way to conduct a series of activities/tasks using a project management model (e.g. waterfall, PERT, agile, scrum), in order to accomplish a unique (one-time) transformation. (Wikipedia)
In order to be able to run effective projects an organisation needs to have project management office in place. The PM office team decides what model should be used for projects, and is responsible for the project management software needed. Running many projects at the same time makes the PM office an program management office.