macbook pro problem with spinning wheel

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Before quitting those applications, close all but a maximum of two windows.
Leave Mail's activity window from the Windows menu open.
Do not leave more than one tab open.
It may be too much for the machine to load at once.
When it comes to Safari, make sure the home page is set to one that fully loads accurately in the browser.
Check the issue does not persist at a wi fi hotspot, and let us know the result.
Also make sure your data is backed up before trying any optimizations.

i open mail and then the activity and i saw that it was sending me password to find any new mails

Did it find any new mails? Or did it just sit there asking for a password?

then how can i see that my home page is set to one that fully loads accurately in my browser???

Find a website you like to visit that doesn't have problems loading. Google and Wikipedia and Apple's own website all should always work.

Go to Safari menu -> Preferences -> Click on the light switch for General.
There you will find a home page field where you can put that website you like.

Ask a friend to send you an e-mail and see if it arrives.

So is everything working?
Have you managed to isolate any webpages that don't work?

I have also had this problem- It seems to be getting worse rather than better and started about a week after I had some problems during freezing at start up of my macbook pro (which was all sorted).