I cannot get out of my iMac OS update loop?

I bought my iMac in 2010 so I'm not sure what model it is & I cannot get into my mac to find out. I clicked on the update OS link provided by apple & my iMac won't update to the new OS. It keeps telling me to quit & re-start. I cannot log in. I'm stuck in this loop.

crwdns2934089:0crwdne2934089:0 crwdns2934093:0crwdne2934093:0

crwdns2934109:0crwdne2934109:0

crwdns2853045:0crwdne2853045:0 crwdns2853046:0crwdne2853046:0

crwdns2889612:0crwdne2889612:0 0

crwdns2944067:03crwdne2944067:0:

Can you get into Safe Mode? Hold Down SHIFT when turning on the computer.

crwdns2934271:0Sun 13, 2018crwdnd2934271:0 S W crwdne2934271:0

Your systems specs: iMac 17" 2.0 GHz Core 2 Duo.

The highest OS your system will support is OS-X Lion 10.7.5

crwdns2934271:0Sun 14, 2018crwdnd2934271:0 Dan crwdne2934271:0

Please look on the bottom of the stand and give us the EMC #.

crwdns2934271:0Sun 14, 2018crwdnd2934271:0 mayer crwdne2934271:0