My kid won't listen to "no"

So my kid is 18 months..

And it's SOOO frustrating when he won't listen when I tell him not to do something.

I just don't know what to do anymore if he keeps doing what I'm telling him not to. I'm trying to hold him away from it or trying to redirect him but he keeps doing these things.

Like some of it is pretty important.. Like crawling onto the table and running backwards. Like when I'm working from home and he tries to be messing with my keyboard.. Like that's my job, that's not ok for him to do. But when I try to redirect him he throws massive fits (so I can't work also)

@Sam I only work evenings so work and caring for our child only overlaps like 1 or 2 hours depending on my husband's schedule. Taking in a nanny or sitter for those hours is a bit silly 🤔

But I'm glad it's not just him tbh 🙂

I tried explaining in words like "don't get on the table because you can fall off" he actually did already fall off 3 times. He basically doesn't care 🙄.

He also doesn't understand that he's messing up my work.