You must register for the exam using the ETS website. On the same site people are able to find other testing information. Once registered you will be given testing location closest to you. Be sure to choose a date that gives you enough time to prepare and have all things in order prior to taking exam.
You can register for the TOEFL on the ETS website (https://www.ets.org/toefl/ibt/register/), which will direct you to the testing center closest to you.
Good luck in your endeavors!
You can register for TOEFL exam on the ETS Official website : https://v2.ereg.ets.org/ereg/public/jump?_p=TEL
They have very simple process to fill in initial details , book exam and choose test centre nearest to you. It also provides you some sample questions and answers to get familiarise with the exam format.
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