If you'll be doing this for a client or professionally, I say
"Assumption is the mother of all f*** ups"
Over the years, the different browsers have gotten better with following html standards.
And what worked for one, generally (maybe 99%) will work with the others just fine.
But it can surprise you once in a while.
A few times, there were some show-stoppers (i.e. user can't click on a link, or can't move away from a page) because of some weird browser problem occuring on one specific platform.
Customer discovers problem using X browser on Y OS. Customer notifies client. Client notifies me about problem.
It can be embarrasing sometimes.
Or the problem only happens on X browser on mobile, but same X browser on desktop works fine.
So my advice is to check on as many browsers (and OS, and mobile devices) you have access to.
As starters, you can download Safari for Windows. (Yeah I know, who uses this on Windows)... but there are a few people that do.
Edge. If you have Windows 10, check it there.
All these browsers are FREE so there's no big excuse not to check on these browsers.
This site may help also determining if you can use an html feature on a specific browser version.
and for mobile devices