Can people who just finished grade 12 get a job this summer?

Sure my grand daughter had a job before she graduated last month

Yes

Yes, of course they can. They are lots of jobs a high school graduate can get.

Most of them will rest for the summer and than head off to college.

I'm 16 in 10th going to 11th I have a job so ya

If that person has previous experience and a strong will/desire, probably he/she can.
Anyone who believes the result, receives it. It is the law of physics and mathematics of the universe.
How he/she could do such a task, is up to him/her. Work in harmony with the law and you will surely receive back what you put out. However, not all can be successful; only the ones who works in harmony with it can succeed.

Yes, well that depends on if you know how to get a job. No offense.

Yes

Yes.

Twelfth grade, Senior year, or Grade 12 are the North American names for the final year of secondary school. In other regions it is also equivalently referred as Class 12. In most countries students then graduate at age 17–18. Some countries have a thirteenth grade, while other countries do not have a 12th grade/year at all. Twelfth grade is typically the last year of high school.