The core idea is that a number of documents1 need to be created which are basically the same but have some different paragraphs based on user choices and are "customised"2 with the name.
For example a letter for a tenant would be "customised" with their name and may include a paragraph if the tenant includes a pet. If they didn't have a pet that paragraph could be omitted. Alternatively the paragraph may be different depending on the type of pet.
Is there any software3 you can recommend to generate these documents?
1. The document format is not a major concern provided it is in a commonly used format, for example Word (.doc or .docx), Text (.txt), PDF (.pdf) etc...
2. It is in quotes, since it is not really customisation more replacing a tag (data slug) with a value.
3. As pointed out in some answers below, there are plenty of scripting language options however I am looking for a no code, or a low code option for this and so a tool (free or commercial) would be preferred.