بعد از کار میخواهم کمی ورزش کنم، چون این هفته اصلا ورزش نکرده ام.

In Farsi, the verb usually shows the subject, so the pronoun is often omitted.

• می‌خواهم = I want
• کنم = I do / I perform in the subjunctive here
• نکرده‌ام = I have not done

Because the -م / -ام endings already show first person singular, saying من is unnecessary unless you want extra emphasis or contrast.

So this sentence could start with من if you wanted, but it normally does not:

• من بعد از کار می‌خواهم... = I, after work, want...
  This sounds more emphatic.

The standard spelling is می‌خواهم with a half-space after می. Many people skip the half-space when typing informally, so you may also see میخواهم.

Standard written Persian prefers:

• می‌خواهم
• نکرده‌ام

Informal typing often gives:

• میخواهم
• نکرده ام

So the sentence is understandable as written, but in careful writing you would usually see:

بعد از کار می‌خواهم کمی ورزش کنم، چون این هفته اصلاً ورزش نکرده‌ام.

After می‌خواهم (I want), Farsi normally uses the subjunctive for the next verb.

So:

• می‌خواهم ورزش کنم = I want to exercise
• not می‌خواهم ورزش می‌کنم

Here, کنم is the subjunctive form of کردن used in the expression ورزش کردن.

A useful pattern is:

• می‌خواهم + subjunctive verb

Examples:

• می‌خواهم بروم = I want to go
• می‌خواهم بخوابم = I want to sleep
• می‌خواهم ورزش کنم = I want to exercise

Farsi often uses a noun + light verb structure, where the real meaning is carried mostly by the noun and a common verb like کردن supplies the verbal function.

So:

• ورزش = exercise, sport
• ورزش کردن = to exercise

This is very common in Persian. Other examples:

• کار کردن = to work
• صحبت کردن = to talk
• استراحت کردن = to rest

So ورزش کنم literally looks like do exercise, but it simply means exercise.

کمی means a little, a bit, or somewhat. It modifies ورزش کنم, so it means the speaker wants to exercise a little.

• می‌خواهم کمی ورزش کنم = I want to exercise a little

Its position before ورزش is natural and common.

In more conversational Persian, many speakers would say:

• یه کم ورزش کنم

So:

• کمی = a little, slightly, a bit more neutral or slightly more formal
• یه کم = a little, more colloquial

Here اصلا means at all in a negative sentence.

So:

• اصلا ورزش نکرده‌ام = I haven’t exercised at all

This is a very common use. In negative sentences, اصلا often adds strong emphasis:

• اصلا نمی‌دانم = I don’t know at all / I have no idea
• اصلا نرفتم = I didn’t go at all

You may also see it written as اصلاً in more careful spelling.

نکرده‌ام is the present perfect negative of کردن.

It is built like this:

• نـ = negative marker
• کرده = past participle (done)
• ام / ـام = I am / I have ending used in the present perfect

So:

• کرده‌ام = I have done
• نکرده‌ام = I have not done

Because the full expression is ورزش کردن,
ورزش نکرده‌ام means I have not exercised.

This tense is natural here because the sentence refers to a period that is still connected to the present:

• this week

That is why I haven’t exercised this week fits well.

چون means because. It introduces the reason:

• چون این هفته اصلا ورزش نکرده‌ام = because I haven’t exercised at all this week

Yes, this clause can come first. Persian word order is flexible enough for that:

• چون این هفته اصلا ورزش نکرده‌ام، بعد از کار می‌خواهم کمی ورزش کنم.

This is perfectly natural and means the same thing. The original version starts with the main idea first, then gives the reason.

Yes, it is a normal and very common way to say after work.

Literally:

• بعد = after / later
• از = from / of
• کار = work

Together, بعد از functions as a preposition meaning after:

• بعد از کار = after work
• بعد از کلاس = after class
• بعد از شام = after dinner

So even though از by itself often means from, in the fixed phrase بعد از, the whole expression means after.

A very natural spoken version might be:

بعدِ کار می‌خوام یه کم ورزش کنم، چون این هفته اصلاً ورزش نکرده‌م.

A few common spoken changes are:

• می‌خواهم → می‌خوام
• کمی → یه کم
• نکرده‌ام → نکرده‌م

In everyday speech, some speakers may even simplify the last part further and say:

• چون این هفته اصلاً ورزش نکردم

That is very common colloquially, even though the written sentence with نکرده‌ام is grammatically more precise for haven’t exercised this week.

The sentence as given is very natural, but Persian word order is somewhat flexible, especially for time expressions and reason clauses.

Original:

• بعد از کار می‌خواهم کمی ورزش کنم، چون این هفته اصلا ورزش نکرده‌ام.

Possible variations:

• می‌خواهم بعد از کار کمی ورزش کنم...
• چون این هفته اصلا ورزش نکرده‌ام، بعد از کار می‌خواهم کمی ورزش کنم.

But some parts should stay together:

• ورزش کنم should remain together as the verb phrase
• بعد از کار should stay together as a time phrase
• این هفته should stay together as this week

So yes, there is flexibility, but not complete freedom.