Sewing machine grabs fabric and won't let go

you do not mention the name and model number of the sewing machine or serger,, you do not say if it's the loose stitches are on the top of the fabric or bottom,, try adjusting the top thread tension and see if that helps,, you might also consider taking the machine back and getting another,, remember before you sew when threading, lift the presser foot up to its highest position before threading

Clean the bobbin case and all the parts under the plate. You may have a bent needle, so replace the needle. The bobbin case has a tiny point on it that catches the thread, that may be broken and missing the thread as it spins.

Sounds like it is not catching the bobbin thread which is how it makes a stitch. Try re-threading top and bottom threads. Or perhaps your tension is far too loose. Adjust tension higher or lower to test.

the looping on the underside sounds like a needle thread tension problem. 1st off check top (needle) threading then turn machine by hand to pick up bobbin thread

Perhaps one of these will help:

New Home Model 532 Sewing Machine Threading Diagram

New Home Model 2022 Machine Threading Diagram

Thread Bobbin on Newhome Sewing Machine

HINT: install a brand new needle. Remove the top thread from the machine. ALWAYS RAISE the presser foot and then rethread the top thread. The upper tension should start out set at the midway point. Use only fresh, good quality thread--AVOID old or bargain bin threads.

If the machine is threaded correctly top and bottom, but is still not catching the bobbin thread, then it's possible the machine is out of time. Search for sewing machine timing or take it for service.

Since it is an older mechanical machine, it is recommended to clean and oil the machine frequently. Oil Before using it if it has been in storage. If the machine is sticky, motor drags, etc., here's a good reference for getting it back in shape:

Wheel on right side that controls the needle up and down is very tight...

try adjusting the top thread tension one number or letter higher
sewing on a scrap piece of fabric till the stitch looks normal.

it's possible that when you broke the needle it caused the machine to go out of time & only a sewing machine repair shop can retime the machine

have you tried using a new needle- if the needle is the slightest bet bent or or damaged it can cause problem with the fabric threads

if the needle is not the correct one for the fabric, it can move or damage the fabric threads

also clean under the needle plate for loose threads or lint also in the bobbin area

tension could be too loose. start with bobbin tension- should allow thread to pass with SLIGHT resistance. then adjust top tension at about 2-3 to start.

try to rethread the machine all the way back to the spool of thread and check the top and bottom tensions on scrap of same fabric