you CAN still participate if you're able! just be aware that due to the short notice and lack of targeted action, it might have a diminished effect - so don't go getting yourself in trouble over this! that said, anything helps
(i'll still leave the post up for posterity)
Please, don't take part in this strike.
Look, I'm pro union and strikes in general, I even worked as a union rep for several years while I worked retail, but this particular strike is ineffective at best and at worst spreading this around will cause well meaning workers to lose their jobs.
I get the desire to call for a strike in order to feel like you're doing something to make a difference, but strikes require a lot of organising and effort, and there is no organisation attached to this, it's just a post with a call to action from some rando on twitter.
Effective strikes don't just happen from spur of the moment decisions, they are typically arranged by an organisation (such as a union) who will coordinate strike action, have an actionable list of demands, and negotiators for the company or organisation they're striking against to talk and negotiate with. This has none of that, it's just a random twitter account telling anyone and everyone not to go to work or spend money, which also allows others to jump on and add their own list of ideas for what the strike should entail (as we see in the "how to participate" screenshots).
The action that the posts are asking for is not well thought out, and won't be effective.
Say you take part and call in sick for work, then tell them you're doing this because you're striking for Palestine. What you've done there is admit that you're not calling in sick, you're just skipping work. So either they tell you "no you can't use your sick day for that", in which case you either go into work anyway or risk a disciplinary and probably punitive action for admitting that you're misusing your sick day. Or they're fine with it, or you don't tell them what you're taking your sick day for, so now all you've done is...use a sick day.
Typically, you don't use your sick days for strike action, because the point is you're striking, you're doing action that will damage the organisation you work for, they're not gonna willingly pay you to do that, in fact they will probably try to fire you for this. This is another reason why having an organisation such as a union to back strike is necessary, because they will typically have funds set aside to support workers on strike so that they can still survive while striking, and they will fight for you to retain your job.
This strike is also on extremely short notice, so bugger-all people are gonna even know about this, which is another reason strikes need to be organised, so they can be advertised way in advance, because a) you want as many people to participate in the strike as possible and b) ideally you want the organisation you're striking against to reconsider their actions because they're afraid of the potential repercussions and bow to your demands or at least open up negotiations before the strike occurs.
Unless a significant portion of your workforce is also doing this, then this is not going to affect your company significantly, which is why the actual organising part of a strike is important, because otherwise it's just not going to be effective as the company can just ignore it. In addition, if you don't tell your company that you're striking then...what is the point in striking?! This is the work equivalent of ignoring your partner in the hopes that they'll realise something is wrong and ask you what's up. Work isn't gonna know anything is wrong, nevermind Israel, so they won't even consider attempting to use any form of political influence they might have to force Israel to ceasefire in order to save their profits (if they even have any).
Some of the actions they ask for are fine but also it's very hit and miss. I don't know what not leaving the house is supposed to accomplish, and not spending money in general isn't going to cause businesses to take the kind of action you want them to, because they won't know what you want or that you're purposefully not spending money, at most they'll just think it's a slow day and wait until you spend money tomorrow.
They reference BDS which is good, but BDS is not just not spending or transferring any money at all, it's a specific list of boycotted companies because they support Israel and profit from their warcrimes. I would recommend looking at their website to see which companies they recommend boycotting, as well as other actions you can do to help:
https://bdsmovement.net/get-involved/what-to-boycott
Declaring a single day boycott of everything is not effective; boycotts need to be targeted, and require a lot of organising, public awareness, and effort to be effective, and generally they need to last longer than a single day.
I get that people want to help and that a strike sounds like a good idea, but you can't and shouldn't do it just based on a random twitter post.
I don't know what the most effective actions are that we can do to help the situation, but it's worth looking into charities you can donate to that are helping Palestinians, look into BDS and their recommendations for ways to help. Write to your political representative to urge them that to support Palestine, sign petitions, and also just generally be publicly pro-Palestine and talk to people about it.
Also, maybe get involved with a union if you can, and your local community. Strikes are a result of community and solidarity, but those things don't just happen out of nowhere, you've got to build the foundations down first and build connections. Plus, you may be able to help convince some people to be pro-Palestine that way and help to combat zionist propaganda.