Do I need a lawyer to file trademarks or patents in Japan?

For question 1, If you are a Japanese, or you have residence or office in Japan, then you could register trademark or patent in Japan without trademark attorney or patent attorney, otherwise you will need an attorney.
For question 2, I do not follow your question, but you should know that trademark is about brand name protection, while patent is about technology protection, there are different, namely a trademark could not be filed as patent, if your question is about this.