what is the difference between have and had and in which situations these words can be framed well
Have is in the present tense and had is in the past tense.
I have a boyfriend (present tense).
I had a boyfriend until he left me for someone else (past tense).
I have a cherry tree in my garden (present tense).
I had a cherry tree in my garden. One night there was a very bad storm and it was destroyed. (past tense).