If you are too nervous to meet, then maybe anonymous online hook-ups aren't your thing? I mean that in a constructive way. There are a lot of people who are very curious about it, but use it as a form of porn rather than ever having the intent of meeting someone. They are called Time Wasters. People who do that make an account, chat someone up, look at a few pics of someone's cock (maybe a face pic as well), but then when it comes down to the question of, "When do you want to meet?" the conversation ends, they log off, and sometimes outright delete their account.
The thrill comes from the chat, and almost realizing the potential to meet someone for sex. Like edging when you jerk off, the greater enjoyment is the play rather than the finish. Except in this scenario, there is someone on the other end who is genuinely interested in meeting, and not participating in someone's game.
On the other hand..
If you are nervous and really do want to meet, then take your time and chat to someone to feel comfortable with them. They might even be open to meeting first to have a simple greeting, like coffee, or a drink. That takes the pressure off of having sex being the first thing you do. It also let's you get a better feel of the person, to see if you even like them, let alone get intimate with them.
There is also Plenty of Fish, which is more dating oriented. You get to make a more robust profile, and meet people who are into a more traditional meeting or relationship.
But, if you really want to meet on Grinder, then make sure the other person knows you are new and nervous and want to take a little more time, with some added patience needed. Just because someone says Hello to you doesn't mean you have to meet up with them in 10 minutes and jump straight into anal sex. Be honest, communicate, and most importantly..don't play games with other people.