What if I get a merit in my one post, but after few days I delete that post. Will my merit stay same?
Yes
The merit is not undone if the post is deleted.
So I can give merit to myself?
There should be warning, you can not give merit to yourself, don't be selfish
There should be warning, you can not give merit to yourself, don't be selfish
I've read somewhere that you can't give merits to yourself unless you are using alt account