Alhamdulillah is written ٱلْحَمْدُ لِلَّهِ in Arabic and means "all praise belongs to Allah" or "praise be to Allah". Muslims say it to thank Allah in good times, after finishing something, after sneezing, and also as a way of accepting hard times with trust.
Bismillah is written بِسْمِ ٱللَّهِ in Arabic and means "in the name of Allah". The full phrase, which opens almost every surah of the Quran, is Bismillah ir-Rahman ir-Rahim: in the name of Allah, the Most Gracious, the Most Merciful.
Allah is written ٱللَّٰه in Arabic, and it is the name Muslims use for the one Creator; Arabic-speaking Christians and Jews use the same word. It is pronounced with a doubled, stretched L sound: al-LAAH.
There are 114 surahs in the Quran. Muslims agree on this number, and every standard printed copy contains the same 114, from Surah Al-Fatihah at the beginning to Surah An-Nas at the end.
The Quran has 6,236 verses (ayat) in the most widely used count, which is the one printed in most copies today. Other early counting traditions give slightly different totals, but this is about where verse breaks are placed, not about any difference in the text itself.
Start small and start today: read a few verses with a translation you understand, at the same time each day, and let the habit grow from there. You do not need to read Arabic fluently or finish the whole Quran quickly; the Quran itself tells believers to read what is easy for them (73:20).
Meccan surahs are those revealed before the Prophet ﷺ migrated from Mecca to Medina in 622 CE, and Medinan surahs are those revealed after it. In the widely used classification followed on this site, 86 surahs are Meccan and 28 are Medinan.
InshaAllah (إِن شَاءَ ٱللَّهُ) means "if Allah wills". Muslims say it when they talk about something they plan or hope to do in the future, as a reminder that every plan depends on Allah.
MashaAllah (مَا شَاءَ ٱللَّهُ) means "what Allah has willed" or "this is what Allah willed". Muslims say it when they admire something good, such as a child, a new home or someone's success, to recognize that the blessing came from Allah.
SubhanAllah (سُبْحَانَ ٱللَّهِ) means "glory be to Allah": it declares that Allah is perfect and far above any flaw or anything unworthy of Him. Muslims say it when they are amazed by something beautiful, when they hear something that does not befit Allah, and as part of daily remembrance.