Compare the structure and bonding in sodium chloride and hydrogen chloride

Sodium chloride is made up of sodium and chlorine.
sodium chlorine would form an ionic bond, which is the transfer of electrons

because sodium is in group 1, it has 1 electron on its outermost shell
because chlorine is in group 7, it has 7 electrons on the outermost shell.

sodium and chlorine both want a full outer shell. therefore, sodium and chlorine will form an ionic bond, and sodium will transfer its one electron to chlorine so that it can lose its electron and get a full outer shell, and chlorine can gain an electron and also get a full outer shell. this can be represented using the dot and cross model. as shown in the picture.
but don't forget to add a 1- charge to chlorine with brackets and a 1+ charge to sodium, also with brackets.

hope this helped.. I know it became really long but I didn't really realise it once I was half way.. anyway, if you have any questions just ask :)