After I originally mistook this plant for Pieris, you've now confirmed its Kalmia latifolia, common name Sheep Laurel or Mountain Laurel. The new leaves appear to be pinkish red in colour, so it might be the variety Kalmia 'Olympic Fire'. Like Pieris, they require acidic soil, so hopefully, you've been able to provide that. The plant looks pretty healthy other than the leaf spot, which is most likely fungal in origin, though I'm not too happy about the plant pot rim left around the top. When planting into the ground, it's important that the plant is placed at the same level in the soil as it was in the pot - the rim you've left means the top part is isolated from the surrounding soil rather than being buried in it, and that might compromise its health. These plants are not particularly susceptible to slug and snail damage anyway, so the copper tape is likely unnecessary, so I'd recommend you remove the top of the pot and reposition the plant if necessary.
Kalmia does suffer from a fungal leaf spot which is specific to them (Cercospora kalmiae) and that is most likely what you're seeing here. It is important the plant is not watered using overhead irrigation, but rather the water is applied direct to the soil around the plant, avoiding the leaves - wet leaves encourages this fungal infection. I'm afraid you will need to use a suitable fungicide, if you have any available where you are https://extension.psu.edu/mountain-laurel-diseases