Im Chinese and my name is 陈依仁 (Chén Yī Rén). Can I use this as my Japanese name, and if so how do I read it in Japanese? Or would it be better to use the Katakana version of my English name which is タン・スジン?
Yes you can of course, as many have said. However, I am not sure why nobody mentioned that you can also pretty much use the kanji in your name and just associate to them a Japanese pronunciation as well.
In fact, I think it's important to notice that when it comes to pronunciation Japanese is quite flexible (especially with proper names) and it is not uncommon to find kanji in names associated to very peculiar readings.
If I check a name dictionary, I can actually find tens of possible readings for 陳. Most are similar to チェン. For example you have じん、しょう、ちいん、ちぇん etc. However, I see also the more Japanese sounding のぼる (given name) or the kind of particular くわおつく (last name).
And actually, I can even find 依仁 with the reading よりひと (a given name).
Given that these records exists you can very well write your name using exactly the original kanji (except for using the traditional version of 陈) and simply say that it is pronounced (last name-first name):
Or play around and find any other combination you like. Maybe くわおつく sounds a bit odd, but if you pick a more standard じん for example, I feel that じん-よりひと or read it the other way around よりひと-じん is quite a cool sounding name. :D
Just from personal experience (purely anecdotal), I came across a few Chinese people who all used their original characters hanzi pretty regularly in work scenarios, normally without furigana (name badges, shift schedules, etc).
Anybody who sees your name written thus should know from your surname that you are not Japanese, they will likely ask you how to read it. The people I encountered would say the closest approximation of their name that the Japanese ear could decipher. I would recommend 「チェン・イーレン」.
Although the plural of "anecdote" is not "data", there are examples of Chinese people using the same characters for their Japanese name (or making only slight changes). One example that readily comes to mind is the instant ramen inventor Ando Momofuku (安藤百福), whose Chinese name is Go Pek-Hok (吳百福).