Get familiar with the following terms:
Threshold heart rate
Max heart rate
Zones (5 zones is the most popular and endorsed by BC, but different coaches have different recommended zones - read about them and pick the one you like the most).
Over the next week, establish your threshold heart rate and max heart rate using tests as prescribed by google. These are good workouts in themselves.
Next you need to calculate your training zones - this is best done using a % of your threshold heart rate rather than your max heart rate, but both should produce similar results.
BC sets out the name of the zones as follows:
Zone 1 - active recovery
Zone 2 - endurance
Zone 3 - Tempo
Zone 4 - threshold
Zone 5 - anaerobic
Now, depending on what you goals are, you can build your training program around the above. i.e. if you have a sportive you would like a good time in, lots of Z2 and Z3. If you want to do well in a time trial, you need some Z4. If you are aiming for a recovery ride or even a zone 2 ride, you will be surprised how hard it can be to keep your heart rate within the boundaries - but it is important to do so! Once you have all the zones set up and put onto your computer (if this isn't possible, consider printing them off and taping them to your bars for a while) you are then in a good position to undertake some structured training - feel free to come back and ask about this, lots here will be willing to help