I have a question regarding taxes and donations to a 501c3 non profit organization:

If I donate money (say $7,000) to the the charitable non profit organization
well i be paying $7,000 less at the end of the year when i file my taxes? or
does that all get broken down in percentages and I only end up paying like $300 less on my taxes at the end of the year?

somebody recently told me that if i donate $7,000 to there non profit charitable foundation then i would be paying $7,000 less on my taxes at the end of the year. Further explaining to me that i have to spend that money
anyways so might as well donate it to a good cause.. is this true?

thank you