Question

how can you determine how many covalent bonds, valence electrons, and if negative or positively charged of an element has from the periodic table?

Answer 1

every element tends to attain stability by attaining nearest noble gas electronic configuration.

for example alkalimetals like Na , K , Rb will loose 1 electron to attain nearest noble gas configuration.

same way alkaline earth metals like Be , Mg , Ca will loose 2 electrons.

halogens F , Cl , Br will gain 1 electron to attain nearest noble gas configuration.

but like C it should loose or gain 4 electrons it is not possible so it shares 4 electrons too attain stability.

finally we can conclude that.

how many electrons needed to reach nearest noble gas configuration those many electrons will gain or share.

metals will loose electrons to reach nearest noble gas configuration