I'm a part-time Ind. Contractor, & earned income on a 1099-NEC. I have a W-2 job too. How can I enter home office exp. on TTax Deluxe for the 1099-NEC to get credits/ded?

Yes, if you are an independent contractor, you can make a home office deduction against your self-employed income if you qualify.

To qualify for the home office deduction, you must meet one of these criteria:

• Exclusive and regular use: You must use a portion of your house, apartment, condominium, mobile home, boat or similar structure for your business on a regular basis. This also includes structures on your property, such as an unattached studio, barn, greenhouse or garage. It doesn't include any part of a taxpayer's property used exclusively as a hotel, motel, inn, or similar business.
• Principal place of business: Your home office must be either the principal location of your business or a place where you regularly meet with customers or clients. Some exceptions to this rule include day care and storage facilities.

Please read this TurboTax article for more information.

1099NEC is for independent contractor self employment income.  

You can enter Self Employment Income into Online Deluxe or Premier but if you have any expenses you will have to upgrade to the Self Employed version or use any of the Desktop CD/Download programs. All the Desktop programs have the same forms.  You just get more help and guidance in the higher versions.

How to enter income from Self Employment

https://ttlc.intuit.com/community/self-employed/help/how-do-i-report-income-from-self-employment/00/26653