So to create a blog, you have to choose one from these two platforms.
Differences between free blog and self hosted blog
There are many advantages and disadvantages in between self hosted blog and free blog which are has follow:
Self hosted blog are paid for to start and run forever (either paying yearly or monthly) Whilefree blog are free to start and run forever except for your browsing.
In self hosted blog, you can have domain name of your choice. eg (www aschoolz.com) is the domain name of this site. While free blog have its domain name combine with the the blogging platform you choose eg (www.aschoolz.wordpress.com) that is, if you choose WordPress for your blogging platform, then if you choose blogger as your blogging platform, your domain name will be attach with blogspot eg (www.aschoolz.blogspot.com).
Self hosted blog last forever when you paid your monthly or yearly subscription (charges) While in free blog, you can only runs your site for some year of 2 to 3 years. And also your account can be block at anytime.
You can have unmetered bandwidth of video time and memory space on self hosted blog but only limited amount of bandwidth, video time and memory space on free blog.
Your blog account will be closed if you do not renew your domain name registration when it expire from it yearly subscription or charges but there is nothing like that in free blog.
From what you read there👆I can easily advice you to go for Self hosted blog/site, so that you can have full control over your SEO of your site and be able to monitor your site. Self hosted blog is good to go for, in terms of bandwidth, monetizing i.e (ways to make money from your blog) and professional blog looking.