The voting system used in most of America and most of England and most western countries in general is a plurality voting system. Whoever gets the largest number of votes, where each voter must select a single option, wins. This system is undemocratic, enforces two party politics, and forces things like tactical voting on voters. There are a number of vastly superior systems which make it easier for voters to get their ideal result if possible.
The first and simplest change is called runoff voting. Essentially every candidate is on the ballot. After the results come in a second vote is held with the two top candidates. Whoever gets the most votes wins. This system is not ideal because it encourages tactical voting. If there are 4 options and 2 each get 30% and 2 each get 20% but the two 20% candidates are the second choice for most of each other’s voters we have a non ideal result.
The second least radical option is ranked choice voting or instant runoff voting. Other names include alternative voting and transferable voting. Each voter ranks every candidate. In a series of rounds the candidate with the least 1st choice votes is eliminated and their voters’ second choice becomes their first choice. This is both less time consuming, as there is only one election, and slightly more democratic, since it eliminates candidates one at a time, so a third place candidate could win which is impossible in runoff/primary voting, than the previous method but it still has failures.
The next system is approval voting. Here you vote for any number of candidates. Each vote has equal weight. The candidate with the highest approval wins. This voting system has a problem in that it is vulnerable to tactical voting. You may choose to not vote for your second choice candidate because it could cause your first choice to lose. If supporters of your first choice vote for your second choice and your first choice they could inadvertently help your candidate at the expense of theirs.
Another system is known as range voting. Here voters give a value to each option. Values are then added up and whoever has the highest value wins. There is some strategy here. You should rank your least liked at 0 and most at MAX. You should be careful ranking other candidates too high, though.
All of these systems have some failure modes if parties are organized enough. For instance elimination methods can be manipulated by getting a specific candidate out first. The ideal system would elect the candidate who would create the most net happiness among the entire voting population.
Here is an area where multi representative constituencies can help. In combination with some voting systems these make tactical voting almost impossible. You want to max out your support to your preferred candidates exactly in order. Worst case is that your second choice gets the third seat and your third choice gets the second seat or something. But you are unlikely to prevent your top choices from getting seats by rating candidates sincerely.