Please follow my instruction if you don't do it, I will provide you a warming letter.

[output]

Could you help me to check the following sentences correct and naturl? My direct manager told me that if I don't do it well, I will lost my job.

Please follow my instruction if you don't do it, I will provide you a warming letter.

 

[emsr2d2]

Could you help me to check by checking if the the following sentences sentence is correct and natural? My direct manager told me that if I don't do it well, I will lost lose my job.

Note my corrections above.

Please follow my instruction if you don't do it, I will provide you a warming letter.

Here are a couple of clues:
1. This should be broken down into two sentences.
2. There is a spelling mistake. It's towards the end.

Now try again.

 

[output]

Let me try again

Please follow my instruction. If you don't do it, I will provide you a warning letter.

 

[emsr2d2]

Let me try again.

Please follow my instruction. If you don't, do it, I will provide issue you a written warning. letter.

It's more common to tell someone to "follow my instructions" but the singular isn't impossible.