How hard is the first relationship?

So I'm 23 and generally haven't really had a proper relationship, I had a long distance one when I was like 17 over Skype and I dated another girl when I was 16 for like a week but then I beat up her brother (There was reasons) so... we broke up...

Since then I haven't dated or properly spoke to a girl I had feelings for since especially about feelings etc and I'm just "scared" for the day I do get a relationship I say something wrong or I shouldn't say and screw the whole thing up...
How hard is the first relationship?
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