Because the rights afforded by copyright laws are exclusive to the copyright owner(s), you will infringe copyright if you do any of those things without the permission of the copyright owner(s) - for example, if you copy or adapt a copyright work, or make it available on the Internet.
The best way to avoid copyright infringement is to ensure that you don’t use anything created by anyone else. Simple as that.
If you do use someone else's work, make sure you have the necessary permissions – this will usually take the form of a license from the copyright owner(s), which you may have to pay for. That's true for anything that goes from sampling music and speeches to visual references on your art cover, movie references or quoting citations.
There are certain instances where you may be able to use excerpts of copyrighted material without a license – for example, if you use a small part of someone else's work for the purposes of criticism or review, or if your use constitutes "fair use" under applicable law (particularly U.S. law) – however, discussion of these exceptions is beyond the scope of this guidance. If you intend to use any part of a copyright work in reliance on any of the statutory exceptions, you should seek legal advice first.
Please note: This is just some basic information about copyright. However, this does not constitutes legal advice – please do not treat it as legal advice or as a substitute for legal advice. Please consult a suitably qualified lawyer on any matters related to copyright.