Kope;
Islam is a religious faith - not a religious fact.
do you believe evolution is a fact or faith?
do you believe atheistism is a fact or faith?
Kope, you seem to have things arse-about-face. So lets start with your second question:
Atheism is a disregard for
all faith, for the concept of faith itself, even. This is because every single faith there ever was simply has no evidence for it's assertions and therefore no support except that which is manufactured in men's minds. Having 'faith' in a thing does not make it true or real. I can understand how a religiously reared person might not be able to see how 'belief' can be omitted but it might help to see that 'expectation' could be substituted. Expectation, in the form of the Hypothesis is built into the Scientific method, and is not there to be believed but to be tested. If the tests (experiments) do not support it, it is modified or debunked and the process of formulation restarts. You can't do this with a Belief.
Belief is a black or white/ right or wrong thing and Atheism is not, it is open ended.
Now, why is that plain assertion not straightforward?
As for your first question, the answer is again quite straightforward, if you want to see it:
Evolution is a demonstrable fact. You can prove this to yourself by making the observations and carrying out the experiments that provide the irrefutable evidence.
Of course, you'll need to start by reading up some Darwin, Malthus, Mendel, etc, but that will provide the basis you need to carry out some simple observations and do some simple experiments , as Mendel did.
You can look at all the different strands of evidence, if your mind is not in a straight jacket, and come to realise how each strand contributes to the inexorable conclusion of the fact of evolution and it's mechanisms.
Inform yourself on Geology, Palaeontology, Archaeology, Chemistry, Genetics, the vastness of time and, most importantly, the scientific method.
For proper understanding you need to rid yourself of Belief. Perhaps Belief is an evolutionary form of mass Psychiatry.