lectures numbers help

https://prnt.sc/iu3x24

how can I change the lecture numbers to have the numbers 1,2,3 instead of 1.1 1.2 etc. the same in topic 2 so that they are from the beginning 1,2,3 instead of 2.1 2.2 etc. someone will say how can I do this or some custom css?
or just remove the word “lecture” with a number so that there is only an icon with the name
Ideally, for some of these 2 things there would be a non-standard css but I will accept any solution:

• This topic was modified 5 years, 7 months ago by dekotar. Reason: adding information