ive upgraded my mcreator mod from 1.16 to 1.18. now its all corrupted

ok so I recently made my mcreator project to 1.18. Now when I test my world, i cant make a new one as the datapacks have errors. so i test on an older world now the dimensions wont even work. I just go through the portal frame! And if i ignite it whilst standing in the portal it just crashes. Please somebody help I have so much progress saved!!