How to read the data dynamically from mongoDb by passing custom dates and batch size

var collection = _client.GetDatabase(_settings.MongoDatabaseName).GetCollection<BsonDocument>(mongoCollection);
var documents = collection.Find(doc => true).Limit(batchSize).ToList();

// I am able to pass the batch size but not sure how to pass the custom dates . this line should be work with multiple collections

Could you please provide simple input data, and the corresponding desired output?