begin

begin /bɪˈgɪn/ verb
begins; began /-ˈgæn/ ; /bɪˈgæn/; begun /-ˈgʌn/ ; /bɪˈgʌn/; beginning
begin
/bɪˈgɪn/
verb
begins; began /-ˈgæn/ ; /bɪˈgæn/; begun /-ˈgʌn/ ; /bɪˈgʌn/; beginning
Britannica Dictionary definition of BEGIN
1 
a  : to do the first part of an action : to start doing something
[+ object]
[no object]
b  [+ object] : to start to work on, produce, or give attention to (something)
c  [+ object] : to cause (something) to start
d  [+ object] : to start to have a feeling, thought, etc. — usually followed by to + verb
— sometimes + -ing verb
2 
: to start to happen, to exist, to be done, etc.
[no object]
[+ object]
— followed by to + verb
3 
[no object]
a  : to have a particular starting point : to start at a specified place or in a specified way
b  : to have a specified quality, identity, job, etc., at the start — + as
4 
[+ object] : to start speaking by saying (something)
5 
— used in an exaggerated way to say that something is not possible

to begin with

1 
: as the first thing to be thought about or considered
2 
: at the start : before the current time or situation