How do i say in french: (don't use translator) last week i was sick and tired. last summer i went to the beach and i went swimming. we saw my grandparents and family. we rode bikes together. last night i did homework and cooked dinner. yesterday i ate lunch with friends and watched a movie.

Hi !!

La semaine dernière, j'étais malade et fatigué(e).
L'été dernier, je suis allé(e) à la plage et j'ai nagé.
Nous avons vu mes grands parents et la famille. Nous avons fait du vélo ensemble.
(you could say = nous avons rendu visite à mes grands parents et la famille = We visited my grandparents and family6 Sounds better in French)
La nuit dernière, J'ai fait quelques devoirs et cuisiné le dîner. (littterally)
La nuit dernière, j'ai fait fait quelques devoirs et préparé le dîner --> better 
Hier, j'ai déjeuné avec des amis et regardé un film.

Add the (e) if you're a girl, only where I wrote it like that (e) . "Malade" is both feminine and masculine. The past participle conjugated with "être" has to agree if "je" is feminine. The other ones are conjugated with "avoir" and don't have to agree with the subject.

hope I helped :)