Obviously, Naruto can't do it himself either, he need's Yang Kurama to help him so does Minato with Yin Kurama. If you read the Manga then you'll know the 8 tails stated that the tbb is the first thing a Jinchuuriki learns when they turn into their Bijuu and Bee stated that the rasengan process is the same as the tbb process. So since Minato already know how to form a tbb due to studying it to make the rasengan then all he needs is the ratio which Yin Kurama can tell him.
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and
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Yang Kurama helped Naruto form the tbb since a jinchuuriki needs the Bijuu's help. Naruto needs Kurama working with him. This is Naruto alone
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and Naruto after becoming Kurama's friend
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. Naruto said him self that he learns thru experiences, he need to know how the ratio felt to be able to use his tail beast rasengan. So what's the differences between Minato who knows how to form a tbb but lacked the ratio? even if Yin Kurama took over and added the chakra, Minato would still feel the ratio which is all he needs.
Plus by your logic Minato shouldn't know how to do a chakra arm since he didn't train to learn it but he used it in the last chapter and most likely because he saw Naruto do it and saw how it works like he did with the tbb, chidori, and kamui or Yin Kurama told him how.