In the following sentences, which one is correcct? If both tenses are possible, what is the differnce?

The summer interships you offer are exactly what I am looking for ( or what I have been looking for)
Both are correct. The difference is only in how you feel about it. If you just feel like you want internships like the ones you're talking about, say "what I'm looking for". If you feel like you've been searching hard for those kinds of internships, and you feel like "Wow, I finally found it!", use the second version.

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