I think you just about covered it all right there. There aren't many options really:

- Play it and finish it anyway

- Look for tips, tricks online or a game survival/strategy guide and practice tips and tricks from that

- Get a friend who is good at the game to play through that part while you watch, then take the controls back when the tough part is past.

- Lower the game's difficulty level if it supports doing that during gameplay. Many games allow this although not all. Some games may require you to restart the game at a lower difficulty level which is also an option.

- Look for game bugs/glitches online which you might be able to exploit such as walking through walls in Skyrim, or using console commands in many games to activate or bypass stuff, or enable various developer/cheat modes such as god-mode or infinite ammo etc. You might just do this to get past a tough spot then revert to normal play for example.

- Go on youtube and watch a "let's play" or other type of gameplay video all the way through, or starting from the place you were stuck at. That is fine for linear games but not so great for open world games or games which have diverse gameplay options/mechanics.

I myself will either slug through the tough spot, or just take a break from the game and not play it for the rest of the day, several days, weeks, or months or even longer depending on my mood when I think of continuing playing it. Other times I may have grown a little sick and tired or bored of the game but just want to see the end to know the whole story for my time and effort, so I might fire up a strategy guide or walkthrough or to a lesser extent fire up some game developer cheat mode things. Normally I usually just play games right through though or just stop playing them.

Put it away for later, I will finish them later, as I'm too stubborn to give up on any of them.

I think I got it on GOG because of some memory of the demo, only to find out that it sucked balls / wasn't for me anymore. It lacks the quality stuff that made some of the other Build engine games (Duke3D, Blood) so great, IMO. The only semi-cool thing I remember about it is some of the music that came with it.

What I usually do in such a case is to either put the game away for a while and try it later, or watch the part of the game where I'm stuck on Youtube to figure it out (mostly with puzzle games and sometimes adventures, it probably does not work so well for other types of games). Unless the Youtube thing counts as cheating already, I don't cheat. That kind of defeats the purpose of playing a game for me.