English Series: Present Perfect

We use Present Perfect Tense when we use it to talk about a something that started in the past and continued until now.

It is made up from: have/has + past participle.

Example:
I have been in Japan for 3 years. (From 3 years ago in the past until now, I have been in Japan. I didn't live in another place.)

[Ref]

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We use Present Perfect Progressive Tense when we talks about how long you have been doing something you started in the past and still continue now.

The present perfect progressive tense has two uses. It is used for:
(1) a continuous activity that began in the past and continues into the present, or
(2) a continuous activity that began in past but has now finished (usually very recently).

It is made up from: have/has + present participle.

Example:
1. The students have been practicing the play since last month.
2. Amanda has been relying on a pay rise to pay her student loan. (Amanda might still be relying on a pay rise, or she might have received the pay rise. You can't tell from this sentence. However, this information is just setting the scene for some more information about Amanda's present situation.)

[Ref 1][Ref 2]

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Perhaps, the correct usage of for and since are relevant to this post.

Since:
Use since + (a specific time) like March 31, or 9:19 a.m., or Tuesday.

Example:
John has helped me since 10:00 this morning.

For:
Use for + (a length of time) like 1 day, or 3 hours, or 5 years.

Example:
John has helped me for 8 hours. (Present Perfect Tense)
Those people went to Europe for 2 months. (Past Tense)

[Ref]