Content Writer/Content Marketing: This is primarily around creating an editorial calendar and strategy around topics to write that would educate an audience on certain topics related to the product or solution that the business is in. For example, a health drink company may want to have a health blog about healthy lifestyles, eating, and drinking. That could also include other types of content like video, social media posts, research papers, and website copy. You would be writing about all sorts of topics, but also still involved with business decision and analytics to improve website visitors and views.
Product Marketing: A wider lense across the strategy of messaging and positioning of products and solutions at a company. This would include some elements of editing and writing, but also overall marketing strategy, campaigns, and planning.
Advertising: There are specific roles for advertising copy writers at many advertising agencies. You would be responsible for creative copy writing for different types of advertising campaigns (online ads, social media, billboards, video, direct mail).
In general, editing and writing is an essential skillset to have in marketing no matter what position you are in. You'll need to communicate effectively across all parts of the job.
Marketing is also a very broad field so you can think about an industry that you enjoy i.e. (Sports, Tech, Music, etc) that all have business marketing roles that utilize these skills.
There are multiple corporations that leverage Communications and/or Marketing to enhance their Training (Learning & Development), Engagement, and general communication/marketing strategies.