Read the article "All the Social Media Apps You Should Know in 2021." (link in reference)

You are starting a new business, select a platform that you plan to use in your digital marketing plan from this list, or find some platform not listed. Tell us what your imagined business is, whether product or service and why you chose the social media platform that you did and how you would use the platform of your choice in your digital marketing plan. Feel free to research your platform further. How does the platform charge businesses for its services? Will you be able to do all the marketing, or would you need to hire a professional?

Reference:

https://blog.hootsuite.com/best-social-media-apps-list/