This sounds like a good idea because you barely have to invest anything into it, a couple of pictures and a copy and paste message and you're sorted. However, from my experience online dating is one of if not the worst way you can build confidence with women, I actively avoid online dating. Whenever I'm bored and want to meet new women, I stand up, put on clothes, walk outside, grab my balls, go to the shop, banter with the guy who works there and buy a pack of gum. Then as I'm walking to the town centre, I stop random people(old, young whatever) and compliment them on something, it makes them feel good and I feel better. Then I see a girl that I like and I get out of my head, walk towards her and tell her that I came to speak to her because I thought she looked nice. How many bad reactions do I get, it still makes the days of the girls who are engaged or have boyfriends.
But guess what, the first time I started doing this, I crapped myself and I'd already spoken to hundreds of girls in my life. It is scary but you will make the most progress doing it this way. You want to make progress, you'll have to do something which will make you crap yourself. Any guy who has got really good at this will tell you, they went through some tough times, some tough nights where they've gone home with nothing and felt like giving up because of the rejection but they've pulled on through and they're getting all the good pvssy.
Doing it all online is basically just pvssing out, grab your balls, take baby steps but actually go and do what you want to do. Any smuch can sit behind a screen and talk to women online, in fact many do and they send women pictures of their penis and tell them what they want to do to them.
And remember, it doesnt matter if you screw up as long as you're learning, find someone to go through it all with you at the beginning because it will make it easier.
EDIT: However, if you dont feel like going hard at the start, begin by being social. Befriend 2 or 3 girls, totally friendzone them and hang out with them(dont fall for them) then learn from how they interact with guys and how to get what you want from them.