Each of these is one question, answered in the first paragraph and then explained properly. No sign-up needed to read them.
To send money from the USA to India you need a verified account, a US bank account linked as your funding source, and the recipient's UPI ID or their bank account number and IFSC code. Setup takes a few minutes once; after that a transfer is three screens.
Send money you earned abroad into an NRE account: the balance and its interest stay freely repatriable and the interest is not taxed in India. An NRO account is for income earned inside India — rent, dividends, a pension — and both its interest and its repatriation are restricted.
An IFSC code is the eleven-character code that identifies one bank branch in India, and it is required to pay money into an Indian bank account. It is printed on a chequebook and passbook and shown in every Indian banking app under account details.
Most of the wait in an international transfer is the debit from your own bank, not the payout. An ACH pull from a US checking account settles over one to three business days; once it has cleared, delivery to the recipient typically happens within 48 hours.
Money you send to India is not itself taxed on arrival — a remittance is a transfer of your own or gifted funds, not income. What can be taxed is what the money then earns: interest on an NRO account is taxable in India and has tax deducted at source, while NRE interest is exempt.