"The end of life" is quite straightforward, but sometimes Bible writers simply call it "the end" or "the end of time". These are both correct and adequate usages. The end of "my life" is the end of time for me. The possibility of this usage must be considered when no other alternative is suggested.

Mark 13:12-13
Now the brother shall betray the brother to death, and the father the son; and children shall rise up against their parents, and shall cause them to be put to death. And ye shall be hated of all men for my name's sake: but he that shall endure unto the end, the same shall be saved.

Here, the Christian is put to death and must endure to the end. Obviously, they can't endure beyond their death, so the end for them is the end of their life.

Luke 22:37
For I say unto you, that this that is written must yet be accomplished in me, And he was reckoned among the transgressors: for the things concerning me have an end.

Yahushua (Jesus) is speaking of the soon end of His life.

2 Timothy 4:6-8
For I am now ready to be offered, and the time of my departure is at hand. I have fought a good fight, I have finished my course, I have kept the faith: Henceforth there is laid up for me a crown of righteousness, which Yahushua, the righteous judge, shall give me at that day: and not to me only, but unto all them also that love his appearing.

Paul is discussing his fight that is now finished. His "fight" and "life" are synonymous and he has reached the end of his life.