No. You are not allowed to copy and paste content in affiliate marketing [in general for any domain] because doing so is against the rights of the person or company who owns that content.
If the affiliate program offers content as one of its support resources for your promotion of affiliate products, you are free to do so.
The ideal technique is to always produce your own original, high-quality content. You can also use other people's work as inspiration for your own content creation.
Make your own content templates based on your needs, and utilize them as frequently as you can.
Here's related information that you may find helpful – 37 Hard Secrets Every Beginner or Intermediate Affiliate Marketer Need To Be Aware Of.
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