Your mini orchid looks to be a Phalaenopsis orchid. There is not much to go on in your image except to answer your two parted question. The raised white spot is not really much of a concern unless there are dozens of them all over the plant. But a single raised white spot could just be a mechanical blemish coming from rough treatment in the store. Does it scrape off easily with a finger nail? If it does then remove it. If it is part of the leaf surface tissue then it is probably mechanical damage.
They dark blotch is a bit more concerning. It is no problem really right now unless it expands in size. It is fungal damage, a sunken area of dead tissue. It will not go green again. But as long as it does not expand, it is okay to just leave it alone. If it expands you can remove that part of the leaf with a sharp knife. You can treat the cut edge with cinnamon. If it were to suddenly expand and take over the entire plant, the plant would die.
Welcome to the site and the Orchid Forums! We have several "threads" here dealing with Phalaenopsis and how to grow them properly. One such thread is 'Supermarket Orchids- Phalaenopsis'. That would be full of helpful information on growing them and dealing with issues.
In brief, bright location, NO SUN, 65-80 degrees, water about every 3-5 days depending upon size of pot, temperature and type of media. Feed once every 4 months.
