Questions about degoogling and privacy

Brave and firefox using google services make them be monitored by google?
I’ve heard links can be faked to look like something but lead to viruses. What are the things to keep in mind when browsing? And what are the actual risks. For example, for malware or anything else thats harmful to get in your device, it always needs to ask you to be downloaded or ask you to write personal info? What is the safety regarding links that open apps automatically, like for discord server links? Is it possible for a re-directing link to gain access on your account?
Ive heard phishing sites can steal info automatically, is that true?
What are the risks exactly with http and with a malicious site you get redirected to? Only that it may read what you write or something else? Do malwares work upon downloading or they need permissions/to be manually installed.