xiěwán bàogào yǐhòu, jìde xiān bǎ wénjiàn bǎocúnhǎo, zài shàngchuán dào wǎngzhàn.

写完 is 写 + 完:

• 写 = to write
• 完 = to finish, complete

So 写完报告 means finish writing the report.
Here 完 is a result complement, showing that the action reaches completion.

Chinese often does not need 了 when the completion is already clear from a result complement like 完, especially in a time phrase such as 写完报告以后.

So this sentence sounds natural as written.
You could also say 写完了报告以后, but it is a little heavier and not necessary here.

以后 means after or afterwards.

In 写完报告以后, it connects the first action to the next part of the sentence:

• 写完报告以后 = after finishing the report

It creates a time clause. A very natural English equivalent is After you finish writing the report...

Yes. These are all possible:

• 写完报告以后
• 写完报告后
• 写完报告之后

They all mean after finishing the report.

Small difference:

• 后 is shorter and a bit more concise
• 以后 is very common in speech and writing
• 之后 can sound slightly more formal

记得 literally means remember, but in this kind of sentence it works like a reminder:

• 记得先把文件保存好... = Remember to save the file first...

So it is not just talking about memory in general. It is telling someone not to forget to do something.

A common pattern is:

• 记得 + verb phrase

For example:

• 记得关门 = Remember to close the door
• 记得带手机 = Remember to bring your phone

先...再... is a very common pattern meaning first... then...

Here it shows the correct order of actions:

• 先 把文件保存好 = first save the file properly
• 再 上传到网站 = then upload it to the website

This pattern is very natural when giving instructions.

把 marks the object as something being handled or affected by the action.

So:

• 把文件保存好 focuses on what you do to the file
• literally, it is something like take the file and save it properly

This is called the 把-construction. It is often used when:

• the object is specific
• the action changes, affects, or disposes of that object
• the verb phrase includes a result or direction, such as 保存好, 关上, 放到..., etc.

A more basic word order would be:

• 先保存好文件，再上传到网站

That is also possible. But 把文件保存好 strongly highlights the file as the thing that must be dealt with correctly.

In 保存好, the 好 is not the adjective good by itself. It is another result complement.

• 保存 = save
• 保存好 = save successfully / save properly / make sure it is saved

So 好 here shows that the action is carried out properly and reaches the desired result.

This is very common in Chinese:

• 看好 = watch carefully / keep an eye on properly
• 准备好 = get ready / prepare well
• 写好 = write properly / finish writing to a satisfactory state

They are similar, but not identical.

• 写完 stresses completion: the report is finished
• 写好 stresses that it is written and in a satisfactory/ready state

So:

• 写完报告 = finish writing the report
• 写好报告 = have the report written and ready / written properly

In this sentence, 写完 fits well because the next steps happen after the writing is completed.

到 marks the destination.

• 上传 = upload
• 上传到网站 = upload to the website

So 到 works like to in English.

In modern Chinese, people sometimes say 上传网站, especially in casual tech contexts, but 上传到网站 is clearer and more standard for learners.

Yes, some parts can change, but not everything.

For example, these are natural:

• 写完报告以后，记得先把文件保存好，再上传到网站。
• 记得写完报告以后，先把文件保存好，再上传到网站。

But the original order is very clear because it sets the time frame first: after finishing the report.

Also, the order of 先...再... should stay the same, because it shows sequence.

It is mainly a reminder/instruction.

Because it uses 记得, it sounds softer than a direct command. It is like saying:

• Remember to save the file first, and then upload it.

So it is more polite and practical than a blunt imperative.

Chinese often omits something that is already clear from context.

Here, after 把文件保存好, it is obvious that the thing being uploaded is the file, so Chinese does not need to repeat it.

If you wanted to make it explicit, you could say:

• 再把文件上传到网站

But the original sentence is more natural because the object is already understood.