Me and my girlfriend who are going to marry in a year... and I am not asking her to get physical with me... I'm asking is just romance over a video chat... and she deny every single time... she keeps on saying I will do everything but after marriage...
She is very much conservative and of old thoughts... we both are 200% loyal to each other...
1. is it good thing to keep on asking her for romance because sometimes I get frustrated.?
2. is it my fault that I keep on asking or is it her fault that she keeps on denying...
3. what can I do to convince her. I've tried almost everything...

You stop asking her. Respect her wishes or leave her alone.

No
Yes
Nothing

You need a new girlfriend.

If you know your girl friend is conservative in her thinking, why are you trying to talk her into doing something she obviously does not want to do?
I don't know how often I have heard about girls doing this and "somehow" somebody else gets a hold of it or the guy gets mad and post it somewhere.
You need to respect her wishes or get someone else. Not every woman wants to be her man's video porn star.