If you are asking whether using the Terms and Conditions from another website may infringe the copyright of the author of those terms and conditions, the answer is a very weak "maybe." Most terms and conditions have such similar language that it is highly unlikely that there is anything sufficiently creative in the T&C to merit copyright protection.
If by "causing legal issues" you are asking whether there are issues related to the website that are not covered by your T&C, that can certainly be the case. If their T&C misses something, then possibly you'll miss the same thing. If there are subtle differences between the websites that require that you have different T&C, then you may miss those.
I have written Terms and Conditions for a wide variety of websites. Even though I know what goes into a basic T&C, I always look at a few other sites in the same or similar business to make sure that no one else has a slightly different take on the issues than I do.
