I think my tallheight is average level infor Japan. I think my height is average for Japan.

I think my tallheight is average level in Japan. I think my height is average in Japan.

Tall and short are adjectives; the noun you are describing is your height. No need for the word "level" here

I think my tall is average level in Japan. I think my tall is average level in Japan.

I think I’m average height in Japan.

I think my tallheight is average level in Japan. I think my height is average level in Japan.

I think my tallheight is average level in Japan. I think my height is average in Japan.

I think my tall is average leveheight is normal in Japan. I think my height is normal in Japan.

Rather than "tall," one would use height when speaking about different people and their heights. When you say average, you would use for instead of in to connect it to Japan. Though, when using normal, "in" to connect it to the word Japan is correct.

Rather than being tall, my shoulder width is pretty wide inby Japan, thus I'm having trouble with that because there are notese standards. Thus/For that reason, I'm having trouble finding clothes that suit for me. Rather than being tall, my shoulder width is pretty wide by Japanese standards. Thus/For that reason, I'm having trouble finding clothes that suit me.

The word "thus" is not commonly used in everyday speech, it would be considered a bit formal or old-fashioned. I gave a more natural alternative. By the way, you can also describe yourself as having broad shoulders (this means your shoulders are wide).

Rather than tall, my shoulder width is pretty wide in Japan, thus I'm having trouble with that because there are not clothes that suit for me. Rather than tall, my shoulder width is pretty wide in Japan, thus I'm having trouble with that because there are not clothes that suit for me.

Rather than tall, my shoulders are pretty wide for Japanese, so I’m having trouble finding clothes that fit me. [(clothes) that SUIT vs FIT. (SUIT) 1. Suit is more for style. 2 .It could also mean ‘appropriate for.’ Ex. 1. Wow! That color really suits you! 2. That outfit is better suited for an athlete than an officer worker. (FIT) This is good for matching body shape and/or size.

Rather than tallOn the other hand, my shoulder width iss are pretty wide infor Japan, thusese standards, so I'm having trouble with that because there are notfinding clothes that suit forfit me. On the other hand, my shoulders are pretty wide for Japanese standards, so I'm having trouble finding clothes that fit me.

Rather than tall, my shoulder width is pretty wide in Japan, thus I'm, therefore I havinge trouble with that because there are not that many clothes that suit for me. Rather than tall, my shoulder width is pretty wide, therefore I have trouble because there are not that many clothes that suit for me.

Rather than tall, my shoulder width is pretty wide inbeing tall, I have more of a wider shoulder width for Japan, thus I'm having trouble with that because there are not clothes that suitare suitable for me. Rather than being tall, I have more of a wider shoulder width for Japan, thus I'm having trouble with that because there are not clothes that are suitable for me.

You would use the word being for emphasis to make sure your point is clear. The word "pretty" is appropriate in most circumstances when speaking or writing informally, however, using it in other contexts can be considered informal. "Are suitable" would make more sense in the context of talking about the clothes.