Do I need to do the physics practicals again

Basically I'm retaking my A levels privately but doing the practical endorsements for physics costs a lot and is confusing. if i failed physics the first time but still passed the practicals can i just use whatever certificate I got then, and does it matter if im doing physics under a different board now?

The practical endorsement (which is what you're talking about) can be carried-forward to your retake, even if the exam board is different.

For example, see this from OCR:

"If I want to retake my A Level exams will I have to redo all the practical endorsement activities?
No. The practical endorsement will not contribute to the A Level grade and will be reported as Pass or Not Classified. Thus this will remain the same whatever your final A Level grade. A pass in the practical endorsement may be carried forward and used alongside the grade achieved in re-sitting the exams, even if this is with a different exam board (using the appropriate entry code)."

Whatever exam board you're using will have a similar statement on their web site somewhere.

thats like a complete response to what i was asking tysm