A quick way to make predictions with your model / tokenizer is with the pipeline() function, e.g.
from transformers import pipeline

# Note: the model and tokenizer directories are usually the same
ner_tagger = pipeline("ner", model="path/to/your/model/dir", tokenizer="path/to/your/tokenizer/dir")

text = """Hugging Face Inc. is a company based in New York City. Its headquarters are in DUMBO,
therefore very close to the Manhattan Bridge which is visible from the window."""

entities = ner_tagger(text)