Complex sentence: It was during this time in a wooden hut at Revdal, he called Hotel Savoy, that Jan was forced to operate on his feet with a pocket knife believing that he had blood poisoning and that drawing the blood of would help.
Split into simpler sentences: It was during this time in a wooden hut at Revdal, which he called Hotel Savoy, that Jan was forced to operate on his feet with a pocket knife. He believed that he had blood poisoning and that drawing the blood of would help.