Which deity to practice can increase your concentration, let you learn Buddhism, and even concentrate on your daily work without distraction?

You have completely misunderstood the practice of "the Lord".

This god is the most suitable Buddha, bodhisattva or protector of emptiness you choose. He is the fruit of your future achievements.

It is impossible for a person to practice "respecting the law" from the beginning, which completely subverts the secret law!

A tantric disciple began to practice the "four plus lines method", which is the basis of the secret method.

The "four plus lines method" has been done, so you don't have to worry about concentration at all, because when the "four plus lines method" is completed, you will have great determination.

There is a secret method that has been handed down, and you have the conditions to learn it. A guru will certainly explain how to practice the "four plus lines". Do you have a secret method? Stealing secrets is a sin, and it is useless to practice without enlightenment.