When an old man celebrates his birthday, you don't need to care too much about what the birthday gift is, because what he values is not the gift, but the thought. As his junior, you should give him more blessings, or give him some very practical things, such as giving him some massage chairs, which are not only for the health of the old man, but also very practical. If the old man is uncomfortable, he can have a massage. Such birthday gifts are still very thoughtful.
My suggestion to you is to give the old man some more thoughtful gifts. What we hope is that the old man can be healthy, so it is best to give him some gifts that bless the old man. Good ornaments, pendants, and jade crutches are all OK. This kind of birthday gift is mainly to make the old man feel comfortable after seeing it.
You can also give the old man some things he likes. You can choose according to the old man's usual habits or preferences. It is easy as long as you can understand some of the old man's living habits. For example, for the old man who likes to drink tea, you can give him some good tea leaves and tea sets.