Will I have to give TET after D.Ed.?

Yes, to get a government school teacher job, you'll need to qualify TET which is also known as Teacher Eligibility Test like:

CTET (Central Teacher Eligibility Test) for CBSE & Central Govt. schools

State TETs like UPTET, HTET, MAHA TET, etc. for state government schools

Clearing D.Ed. + TET = your pat