Hello there, you are probably here because you have a question regarding a ruling on a card, or a scenario you want to know how would play out etc. The good people of this site will attempt to help you as best they can, myself included. If you have just started playing the game, check out the official rulebook first here: https://img.yugioh-card.com/en/rulebook/SD_RuleBook_EN_10.pdf
To get the most out of this thread, I hope you will follow my suggestions written below, these are not rules, obviously forum rules apply, but I can't tell you how to post, but I think you'll find this thread better to use if you follow my suggestions:
Staying on topic is important, this is for asking and answering questions, not for discussing cards and Deck builds, you can post those here: http://neocardmaker.com/forum/index.php?/forum/15-yu-gi-oh/
Questions about custom cards is not discouraged, but be aware that not every situation exists in the real game, so your custom card scenario may not be answerable. Your card may have a real counterpart, so look up cards with similar effects and check their rulings before asking here.
Try only to post a single question at a time. If you have similar connected questions, feel free to ask them, but try not to make a list of 10 random questions, not only are you unlikely to get a response to every question, but it spams the thread as well, which nobody likes and may be against forums rules.
Post the full card names if possible and avoid using acronyms that may be too obscure or fan names, memes etc. While most people know that MST and BTH stand for Mystical Space Typhoon and Bottomless Trap Hole respectively, when the card is very new, or it's a rarely used card, say the full name, or even better, post an image or the card text and other relevant information.
When responding to a post, linking to a source is helpful. Sometimes, that isn't possible, or the question is so simple that it isn't needed, but it helps give credibility and gives a "case-law" so to speak.