1.DO YOU BELIEVE OR KNOWN GOD IS A PERSON SITTING IN HEAVEN.
2.WHO WILL GUIDE AFTER DEATH.
It is essential to believe in God, Heaven and such religious concepts. It does not matter who the real god is or where the heaven is. These things will vary depending on the religion. If you are a Hindu you will believe in many gods and if you a muslim you will believe in one god. It does not matter. What matters is that you should believe in one religion and follow the prescriptions of that religion. For example, if you are a Christian you should go to church on every sunday or if you are a muslim you should donate one sixth of your income.
If you sincerely follow such religious prescriptions for a length of time your mind will get maturity to understand who god really is and what happens after death.
Getting the mental maturity is essential pre-requisite to start the spiritual education program that will lead to enlightenment (which means one no longer believes in God because he will know who God is).
Asking questions is very important part of spiritual education program. The answers that you get will be different depending on which expert you ask. (Try asking the same question to a Islam Expert or Christian Expert). You may accept whichever answer is comfortable to you and proceed in that particular spiritual educational program.
My answer to your questions are as below:
1. No. I do not believe in God to be a person sitting in Heaven
2. There is no need of any guidance after death.
Thanks for posting these questions to me.