There are many museums nearby.  Our favourites include

Maeght Foundation.  Fabulous hilltop art musem near Vence.   Giacometti Statues, Picasso, Calder Scultptures, Chagall, Leger - All in an amazing modern building up in the cool of the hills and woods and next to Vence

Picasso Museum in Vallauris with the Chapel he decorated also Madoura his publishers who still sell autrhorised Picasso works.  Quite a small museum but you can buy proper genuine Prints and Pottery at Madoura.

Leger Museum ,  The National Museum for Fernand Leger in Biot.  Also in Biot there is a glass museum ( as yet unvisited so no comment )

Matisse Musem Musee Matisse in the Hills just outside Nice
Set in gardens and Olive Groves

Villa Ephrussi Rothschild and Villa Kerylos on Cap Ferat
Amazing Locations , Villa Kerylos is a recreated Greek Classical Villa, with the quayside in Beaulieu sur Mer nearby for Lunch