Learn Portuguese (Portugal): A mulher organiza o evento para ajudar a comunidade. - The woman organizes the event to help the community.

In English, you can just say "to help" to show purpose. In Portuguese, when you want to express "in order to" do something, you must use the preposition para followed by the infinitive verb. So, para ajudar literally means "in order to help".

Could I use por instead of para in this sentence?

No. Learners often mix up por and para, but they have different jobs. When expressing a clear goal, intention, or purpose (the reason she organized the event), you always use para.

Is organiza a regular verb?

Yes! It comes from the regular verb organizar (to organize). Because the subject is A mulher (she), we drop the -ar ending and add the regular third-person singular ending -a, giving us organiza.

How do I know if comunidade is masculine or feminine?

Comunidade is feminine, which is why it uses the feminine article a. A great trick to remember is that almost all Portuguese nouns ending in -dade are feminine, just like a cidade (the city) or a universidade (the university).