Don't listen to what Kaafir websites say. Obviously they will lie. They hate Islaam and hate Muslims. What prevents them from lying about Islaam or lying about any Muslims or Muslim group? That's what they do. We expect it from them.
If you want to learn about the Islaamic Conquests, you will have to put in some effort. Don't suffice with a few posts the members may post in this thread. Do your own research. I suggest reading Imaam al-Waaqidi's series on the Islaamic Conquests, such as "Futooh-ush-Shaam", "Futooh Misr", "Futooh-ul-Iraq", etc. Start off with Futooh-ush-Shaam. You can find the link here:
Start off with this book. Read it fully. You will learn a lot, In Shaa Allaah.
Don't say "the book is long so I won't bother reading it." That's not the kind of mind-set to have. Generally, to achieve good things, some effort has to be put in. Remember the Arabic saying:
من طلب العلى سهر الليالي
"Whoever wishes to attain loftiness must burn the midnight oil."
Study hard. But more than that, enjoy your studies. This Kitaab is particularly enjoyable. Hadhratji himself (Maulana Maseehullah رحمة الله عليه
) used to give Bayaans on it in Jalaalabad.