I'm still having them.

I'm not attracted to men but mainly shemales and cocks. What is the next step?

Don't hesitate. Get out there and go for it. I felt the same for years and finally tried it. Wish I had done it earlier. wished so many great sexcapades with the guys.

Fantasy is always more fulfilling, and better, than reality!
A lot of guys that really are 'straight' sometimes wonder, and fantasize, especially here, and seeing beautiful penises.
Nothing wrong with liking a nice penis!! you have one, and nothing about liking that, or liking how others look, or even getting off, thinking, imagining, fantasizing, makes you gay.
Nothing wrong with being gay, and a lot of my best friends are gay!
Your sexuality is yours to define, however you choose to define it! If you like getting off to something, that is yours to LOVE!

I would like to have a younger guy suck me first time

To answer your last question first, yes, your cock is very suckable. But I think you already knew that and were just fishing for compliments.

Now, to address your issue about wanting to get it on with a man: DO IT! First of all, it is entirely normal for a straight man to have dreams and fantasies about man-on-man sex, just as it is entirely normal for gay men to have straight dreams and fantasies. So turn these fantasies into reality and see how it suits you. There is a possibility that you're really bisexual and a very remote possibility that you're really gay. But more likely you're just a straight man who is just curious about gay sex. After you've tried it out a few times, you'll know.

And let us know how it went.