Problem with games and lag

There is a problem with the games and more precisely with Fortnite.
Windows 10 went great, but with Windows 11 you can hardly play lag.
What would you advise me? It is also noticeable for slower work than windows 10.
I'm still with the HDD, but I'm considering replacing it with an SSD.
I use Lenovo 520-15IKB (Type 81BF) Laptop (ideapad) - Type 81BF Processor
1x Intel Core i5-8250U Processor (Core i5-8250U)
Memory
1x 8GB DDR4 2133