Non-Muslim websites range from blatantly hostile to factually wrong, and only Islamic websites run by Muslims can provide the true picture. Check telescopic.
The Quran and Hadiths must be used to back up the material on these websites. The Quran is Allah’s (swt) word, given personally or through angel Jibril (gabril)(AS) to Muhammad, the last and ultimate seal of the prophets (pbuh). As the verses were revealed, Prophet Muhammad (pbuh) would recite them to his companions, who would remember them, write them down, and distribute them to the Muslim community.
After you make the “shahada,” you are considered a Moslem. This can be done alone, although some people like to have a witness to their conversion; nonetheless, it is not required in the steps of how to convert to Islam because Islam believes that God is your witness. There are some forms of worship that must be performed when you convert to Islam.
The Hadiths are the sayings and/or actions of the prophet Muhammad (pbuh) that were observed by the prophet Muhammad’s companions and then recorded. Since Muslims believe that Allah’s (swt) prophets are clean and innocent, Allah (swt) would only choose the best among men who have been tried in their life to guide those who have strayed from the path.
(Chapter 2, Verse #136, Quran Al-Baqarah)
These few hadiths were then examined by Imams to see how many individuals were present when the prophet Muhammad said or did something, if the hadith was backed up by everyone present, and if the narration of the hadith was strong or weak. The hadiths were only deemed credible after numerous examinations. Imam Bukhari, Muslim, Tirith, Nazari, Abu Dawud, and ibn Marjah (may Allah(swt) be pleased with them all) have the most comprehensive collection of hadiths.
You can only make a decision based on the information you know, and if that information is erroneous, your decision is almost certainly incorrect. Your faith’s judgement is for your eternal soul, and on the Day of Judgement in Allah’s (swt) court, every good and bad deed will have to be accounted for. No one will be able to claim ignorance because Allah(swt) says in the Quran that He sent messengers to numerous nations.