A decent free system cleaner is C-Cleaner (I won’t say what the C stands for but it rhymes with Frap)
As for anti-virus and anti-malware I usually recommend Panda and MalwareBytes.
Both have free versions available, auto update themselves and have minimal intrusion on the running of the PC/Laptop unlike other well known similar products.
Please excuse spelling/typos. Apart from being a clot it turns out I had one on my cerebellum that's now causing various problems!