If Amorim can put United in a better situation at the end of the season, of course, he will get a better chance for next season. At least next season they will have more confidence in building their team with some new players.
Amorim's challenge this season is quite tough if he doesn't get the new players he wants. But he might be able to stay and improve his players' abilities a little better.
It wasn't an easy job because Ruben Amorim came when Man United was in a slump and what was worse Man United did not have much money left. Therefore, Amorim must be really wise in determining which players he must release so that Man United can quickly get additional funds to bring in the new players that he wants. With their current achievements, it is clearly not easy to make a quick sale at the price they expect, therefore, he really has to slash prices so that teams will be interested in the players he wants to sell.
I will honestly advice that Amorim makes good use of whatever finances that will be available for him for player purchases to get the right players to help the team especially in defense and midfield because repeating same mistakes as Ten Hag when he was still in charge as United’s boss will also cost him his job. I keep blaming Ten Hag cause he had his chance to change things but his transfer strategy was inefficient.