Hello Madhuri, you can categorise personal transactions to an Owner's Equity account rather than business expense categories.
If you haven't set up the account yet, simply navigate to the Gear icon> Chart of accounts> New account. In the account name field, enter Personal Transactions. Select Equity for the account type, and choose Owner's Equity for the detail type. Then you can fill out the necessary details. After you've finished, click the Save button.
Once done, you can then categorise your personal transactions to that specific account. This keeps them out of your Profit & Loss and ensures they won't affect your MTD submissions to HMRC.
Alternatively, you can exclude some personal transactions from the Banking tab if you don't need to categorise them. Just select the specific transaction and click Exclude.
If there's anything else you need help with in QuickBooks, please don't hesitate to come back.