Start by making sure your battery is fully charged. Then you need to focus on this code:

CEM-6 C48 Transponder Type. Signal Faulty

see here: https://www.dtcdecode.com/Volvo/CEM-6C48

Have you done the basic power/ground/trigger circuit test? This is performed at the coil on plug connectors. Doing this will eliminate the majority of searching to see what's not working. To perform test you; 1. Remove the air plenums above the top of the acmshaft cover 2. remove the 5 torx screws h...

The codes your showing sounds like the CEM has issues, it's easy to remove & check (video's on You Tube) These components all control/communicate w/ each other. Delete the codes and see if they repeat. A company in Canada rebuilds these w/ warranty.

Maybe try sending a pm to forum member "Jagger" - from his posts he appears to be capable of handling certain programming on-line.

Have your friend clear the codes and see what comes back. I suspect most of the codes he pulled are artifacts because CEM-6C48 will prevent the starter motor from turning over.

Sunroof drain - a common fix here as the tube is too short (Me thinks it shrinks with age) is to cut it at the top of the pillar and use a tube that has a ID that snuggly fits the OD of the existing tube - making it so about an inch of gap to provide the needed length. Basically it is acting as a co...

Well your code says you have a crank shaft sensor issue. A failed unit will cause a non-start. I would track the harness back - look for a compromised wire/harness/junction. Not sure if there is a fuse. If you have a VOM you can use that to help. Any information on the vehicle before you bought it (...