If you intend to do something, it means you plan to do it. You have the desire or idea to do it in your mind, but the action has not been performed yet. For example:
I intend to go to grad school next year.
The Olympic athlete intends to become a coach after retiring from competition.
Something you intend to do is still in the future or in your thoughts. But something you tend to do is in the present and past - it is a real action. If you tend to do something, it means you generally or typically do it.
I tend to be the first one to arrive at the office in the morning. or ( I typically arrive first)
Children tend to prefer sweets to vegetables. or ( children usually want to eat sweets, not vegetables)
The summers tend to be rainy in this part of the country. or ( it generally rains in the summer)
You can only use intend with planned ACTIONS, but you can use tend with actions or with thoughts, beliefs, preferences, or states of being:
I tend to like comedy movies better than action movies.
I intend to see the new romantic comedy.
He tends to be shy in social situations.
He intends to take public speaking classes to improve his confidence.
The powerful antioxidants in oranges fight off oxygen free radicals that deprive healthy skin cells of oxygen by stealing oxygen molecules from them. These free radicals play a significant role in creating wrinkles in skin and also lead to sagging of cheeks. The significant amount of calcium in orange peels is also very effective for protecting against premature aging of the skin.