If I come for entry visa in Portugal. I can apply...

If you are in Portugal via a tourist visa, it is not possible to apply for a residence permit except by obtaining a work contract, study visa, or marriage (then reunification) that requires applying for a new visa from outside the country

Requirements for obtaining a residence permit:

In order for a person to obtain one of the aforementioned residence permits, he will need to meet some of the requirements:

• A valid passport
• Good conduct or clean record
• Fluency in the language

Obtaining health insurance

• Pass a health examination that proves your ability to work or study

You have the financial ability to spend on yourself

• As for what he will not work, he will need to provide a letter from the employer accompanied by a job offer and a description of the work he will do
• For those who will study, he must prove that he has received the acceptance letter from a university
• For those who join his wife or wife, the marriage contract must be presented

If all documents are available, you can start the process of requesting the residence permit that is appropriate for you.

However, before taking any step, you should consult with the Portuguese embassy or consulate in your country in order to inform you in detail of all the steps that you must take.