However, if we were in the past, when the competition was not so intense, there are some kinds of jobs, like teachers and doctors, can provide us secure future lives.
you already used
intense in your first paragraph, try to use synonyms like extreme, fierce etc..
Also, there
were some kind ..., that
provided us...
Something like this is always happening.
This happens very often nowadays./ We can see this very often nowadays.
So people in the past may identify a job that promises a bright future for them much more easily.
Instead of writing 'people in the past', you can start sentence like 'Earlier, people'.
This can be write like 'Earlier, people were able to identify the jobs...
And, don't try to scribble your thoughts directly on paper. Write-read-write-read each sentence many times before making it final.