Religions are systems of faith and the belief and worship in superhuman or typically godly power(s). Note that I am not a theologist and some things I may say are possible to be incorrect so take anything I say with a grain of salt.
The largest and most widespread religions group is the Abrahamic religion group, including Islam, Christianity and Judaism. The grouping is named after Abraham, considered to be the first partriach and to have made a promise to God, that being that God would offer Abhraham protection and land in return for the belief in God.
Following the Abrahamic group, the Dharmic religion groups are the second largest groupings having Hinduism, Buddhism, Sikhism and Jainism. 'Dharmic' comes from the Sanskrit word dharma which generally means cosmic law and the path one must follow to live in harmony.
BuddhismBuddhism believes that life is suffering. Suffering comes from desire, and desire ends in suffering. To escape the cycle, one must follow the Eightfold Path; right views, intention, speech, action, livelihood, effort, mindfulness and concentration. Following these paths will result in nirvana, liberation from being rebirthed.
ChristianityChristianity believes in the Holy Trinity, the Father, the Son and the Holy Spirit, together forming a singular God. Christianity teaches that Jesus Christ is the Son of God, who died for the sins of humanity, was buried, rose from the dead on the third day and ascended to heaven.
HinduismIn Hinduism, there are generally 4 main Purusharthas (duties) that any believer should follow. Those being becoming wealthy, feeling fulfilled in your desires, liberation and righteousness. After death, you are reincarnated based on your karma (i.e. everything you do). Karma dictates what you'll be reincarnated as. For example, bad karma could result in being reincarnated as an insect or plant.
IslamIslam believes that there is only one God, with Muhammad being the final prophet. Islam has five pillars that all believers should follow; faith, prayer, charity, fasting & pilgrimage. When you die, the angels Munkar & Nakir question you about your faith. Depending on your answers, you'll either go to the garden of Paradise (Jannah/heaven) or recieve punishment.
JudaismJudaism believes that God chose the Jews as His people as part of the Abrahamic agreement with God where Abraham would receive protection in exchange for worship. Judaism believes that the Messiah will come and rejects Jesus as the messiah and that God is actively involved in world affairs, affecting everything people do.
ShintoismShintoism is an ancient Japanese religion and evolved from folklore. Shinto, meaning 'The way of the Gods' in Japanese, believes in Kami, gods or spirits which live inside nature, ancestors and concepts. There are two main concepts in Shintoism, Kegare (impurity) and Harae (purity).
SikhismSikhism believes in one God, Waheguru. Sikhism rejects the caste system and gender discrimination, advocating for equality. In Sikhism, you must lose your egoism completely in love for God to merge with him. When one is respectful of others, it helps them become closer with God.
Taoism'Tao'/'Dao' literally translates to "Way" or "Route". Tao is the natural flow of the universe. Principles of Taoism include simplicity and living in harmony with nature. In religious Taoism, one seeks spiritual immortality through meditation, which means your spirit lives on after the death of your mortal body.