It's pretty simple dear. For the bigger font of the whole sentence, you can use "#" sign before the start of the sentence.
Example. It's Nice Meeting you
To make it Bold.. I'll use
(# It's nice meeting you)
It's nice meeting you
(## It's nice meeting you)
It's nice meeting you
(### It's nice meeting you)
It's nice meeting you
(#### It's nice meeting you)
It's nice meeting you
(##### It's nice meeting you)
It's nice meeting you
(###### It's nice meeting you)
It's nice meeting you
and for the paragraph breaks, do the google search for paragraph divider in png
I think thhis is enough for you to understand
Dear knowkrish thank you for it.please tell me more and where I can find such information about a large volume of knowledge about what we're talking about. I'm New and I'm ready to work for STEEMIT. ###You can see my works and comment.
Rarely when people help newbies, you already have a great experience, I'm happy for you,you have cool achievements .
Respect Spyke
##Damn #thank you ###great ####look ###I #already ##happened