at the moment I'm taking 14 units of lantis in the morning and 4 units of Humalog with meals .
On fixed doses of bolus you should have been given some advice on how many grams of carbs that dose was designed to cover.
The first thing to figure out is, is 4 units actually covering your meals? What is your blood sugar before eating and bolusing and 2 hours after eating?
If it's covering, you can work out how many grams of carbs it's covering by working out how many grams of carbs are in the meal you ate that turned out to be well covered by 4 units. Then divide by 4 and you'll have a good idea that 1 unit covers X grams of carbs.
Then for food you can work out how many grams of carbs is in what you are going to eat, divide by X (of 1 unit covers Xg of carbs) and that gives the number of units required to cover it.
That's your insulin to carb ratio. And that's carb counting. Do bear in mind that the I:C ratio might be different at different times of day, or at weekends, or depending on activity level.
There's a free online NHS course on carb counting -
https://www.bertieonline.org.uk
It is hard to accurately work out how many grams of carbs are in a plate of food you are presented with at a restaurant, much easier at home where you're cooking and have weighing scales etc. But the carbs & cals book or app is good with pictures of food/portion sizes to give a good idea of carb content. But it would be good to underestimate to avoid giving too much insulin.