Simultaneous appeal to several employers: is it possible?

Question

Career in IT

It's time to look for a job. I'm looking for the first time. Prior to this, the work itself found me. And I caught myself thinking that I don’t know how to act in a hypothetically possible next situation.
Employer_1 agreed to hire me. And I suddenly inform him that while Employer_1 was making a decision regarding me, I turned to Employer_2, and as a result, Employer_2 accepted me, and accepted me on more favorable terms. What should I do:
1) if such a situation is admitted?
2) in order to prevent such a situation?
And in general, is it correct to start negotiations with several employers at once? Probably yes, but only when it comes to the first stages of selection, when, for example, a test task is being performed. Is everything right?

Answer 1

yes, correct. and even report it to employers. you choose the best offer, it's natural.
in fact, the interviewer from hr will ask you this question at the social security. "Are you considering offers from other companies at the moment?". just don't lie.

Answer 2

So it is necessary.

Answer 3

You go to the store for potatoes. She's there for 20 rubles. You go to the next stall, and there are potatoes for 10 rubles.
You don't owe anything to either the first or the second.

Answer 4

So necessary

Answer 5

I’ll answer off-topic - beat this infantilism out of yourself, you don’t owe anyone, but you put restrictions on yourself, it’s hard to live with such an approach