Grandparents in Madrid

Hey guys! My first time using reddit... :)

I am here cause I don't know where else to look for the answers.

Just moved in my grandparents to live with me in Madrid, as they had no one to take care of them back home in Stockholm. It has been nice to have them here, and we enjoy time together, but whenever I work I notice they get very anxious of what to do with themselves.
They have been very independent all they lifes in Sweden, but here not knowing the language, even groceries are a struggle...

Two questions:

1. Is there any place / group / activity you recommend me pushing them onto? They speak English well so it can be international group of people, but something adjusted to their age (late 80s). I want them to slowly adapt this place as their home and it is not easy.
2. First time I will be organising such an event. My grandpa is turning 90 end of this year, and I would really want him to feel seen. Nobody ever really made an effort before for them to celebrate them. He hates physical presents so I am looking for some experience type of present. Any ideas?

Thanks guys in advance :)